From majordomo-owner@berlioz.nsc.com Mon Oct 13 13:48:02 1997 Date: Mon, 13 Oct 97 13:46:30 PDT To: jmoss@rockie From: majordomo@berlioz.nsc.com Subject: Majordomo file: list 'laser' file 'laser.9709' Reply-To: majordomo@berlioz.nsc.com Content-Length: 160698 -- >From owner-laser Tue Sep 2 07:24:58 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA22998; Tue, 2 Sep 97 07:24:58 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Date: Tue, 2 Sep 1997 10:16:29 -0400 Subject: [LASER] A Low Noise PIN diode Laser Receiver ! Message-Id: <19970902.101632.11918.4.K3PGP@juno.com> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 2-3,6-13,16-17,19-26 From: k3pgp@juno.com (John K3PGP) Reply-To: k3pgp@juno.com (John K3PGP) Sender: owner-laser@berlioz.nsc.com Precedence: bulk After a couple of good sunny days it's now raining AGAIN! Fortunately I got a lot of my outdoor work completed and had some spare time last night and worked on my backlog of laser stuff. To those of you that have been patiently waiting for some details on a low noise laser receive front end, the data has been posted to my web site. >From the main page follow: * Construction Articles * A Low Noise PIN diode Laser Receiver ! This receiver is nothing fancy as it's built out of stuff you can get at Radio Shack for the most part and uses tin cans for mounting and shielding. For those of you that got v1.0 there have been a few minor revisions and the current version is 1.0a. John K3PGP@juno.com http://www.qsl.net/k3pgp -==- >From owner-laser Tue Sep 2 08:36:48 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA25324; Tue, 2 Sep 97 08:36:48 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970902103109.00810b90@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Tue, 02 Sep 1997 10:31:09 -0500 To: laser@qth.net From: "Art Allen, KY1K" Subject: [LASER] listserv operational? Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi everyone, Just before we got the word about the listserv address change, I posted 2 messages to the laserlist. Both bounced. So, Im not sure if they ever made the list or not. One of them was about the Sharp tech fax system, and the other was about propagation of 1.3 and 1.5 um signals in free air. Did these messages make it to the list or not? Let me know, I can repost if needed. GL and good dx. Art. >From owner-laser Tue Sep 2 10:39:55 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA00615; Tue, 2 Sep 97 10:39:55 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Date: Tue, 2 Sep 1997 13:24:47 -0400 Subject: Re: [LASER] File Transfers Message-Id: <19970902.132806.16270.6.K3PGP@juno.com> References: <199709021642.JAA21392@fmswksn06.azfms.dot> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 0-4,6,8-19,22-25,31-37 From: k3pgp@juno.com (John K3PGP) Reply-To: k3pgp@juno.com (John K3PGP) Sender: owner-laser@berlioz.nsc.com Precedence: bulk On Tue, 2 Sep 1997 09:42:13 -0700 c1040@azfms.com (Rusty Carruth) writes: > >Hmm. What's wrong with a directory with permissions >777. Or possibly a directory with permissions that >allow writing only (lots of places call that directory >'upload'), then a cron job to periodically move >anything there that does NOT reproduce a name already >present in the destination dir, to the destination dir >for all to see. > >Did that make sense??? > >rusty > ----- You need to take this up with Al, K3TKJ. It's his system NOT mine! I'm co-sysop of the laser listserve not the system it runs on! We really could use a temporary place to stick all the data that people want to send but so far I can't seem to get anyone to fix the problem with the laser ftp directory... ----- PS - I would appreciate it if people would send Email either directly to me or to laser@qth.net and NOT CC stuff to both! Thanks to the speed of our host system anything that goes to laser@qth.net automatically ends up in my mail box just as fast as it does going direct! I am receiving over 150 pieces of Email a day as it is and I don't need more than one copy of everything. - THANKS! - John K3PGP@juno.com http://www.qsl.net/k3pgp -==- >From owner-laser Tue Sep 2 10:39:59 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA00629; Tue, 2 Sep 97 10:39:59 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Date: Tue, 2 Sep 1997 13:28:04 -0400 Subject: [LASER] Copies of posts Message-Id: <19970902.132806.16270.8.K3PGP@juno.com> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 0-14,17-35,39-40,43-44,46-47,49-50,53,56-57,61-63, 70,73-82,84-90 From: k3pgp@juno.com (John K3PGP) Reply-To: k3pgp@juno.com (John K3PGP) Sender: owner-laser@berlioz.nsc.com Precedence: bulk Copies of posts as received through laser @ QSL . net ----- Return-path: Reply-To: "Art Allen, KY1K" To: laser@qsl.net Date: Sat, 30 Aug 1997 08:01:17 -0500 Subject: [LASER] Sharp tech info Message-ID: <3.0.1.32.19970830080117.007fa5c0@colby.edu> Hi Everyone, Sharp makes PD's and laser diodes-they claim to be the #1 in this field. They DO NOT have a WWW site for optoelectronics but they do have a free fax on demand system. The fax on demand is still under development and alot of laser stuff isn't on it yet. The number is 800-833-9437. enjoy, and good dx... Art. ----- Return-path: Reply-To: "Art Allen, KY1K" To: laser@qsl.net Date: Sat, 30 Aug 1997 09:08:23 -0500 Subject: [LASER] 1.3 and 1.5 um laser propagation Message-ID: <3.0.1.32.19970830090823.00809390@colby.edu> Jim and Dave, 1.3 and 1.5 um lasers will propagate better in air beacuse they are scattered less due to the longer wavelength. For LONG HAUL free air, these wavelenghts will get though the atmosphere better than HE or 780 nm IR! The best info I have to quantify the difference in propagation is that the erp at the receiver is 16+ times better every time the wavelength is doubled (assumes all other factors remain constant). A 1.5 um laser compared to a HE-NE is going to provide (1.5/.632)^4 increase in erp-an erp of 31.7! The difference between hene and IR (780 nm) is (780/632)^4 - and increase of 2.3 in erp! Please note, this relies on a somewhat gross oversimplification and rounding of Rayleigh and Mia and some major assumptions are made in order to come up with these figures. These figures are just a better estimate than an estimate that is made without taking into consideration these factors. Does this sound like a run-a-round? YEP, you bet-one could spend their entire life coming up with a better approximation!!!! If I remember correctly, there was a problem with 1.3 or 1.5-I can't remember details, but it had something to do with some absorption or adsorption of an atmospheric gas (cant remember which one) that peak at that lambda. One of those freqs is limited severely in the atmosphere due to this factor, wish my memory was better. Incidently, optics for these frequencies are specialized and not widely available and there are losses when visible lambda optics are used at 1.3 and 1.5. TX and RX products in this frequency range are usually fibre optic. Interfacing to and from fibre optic is easier said than done, I think the best interface has a 3 db+ loss FOR EACH transition. Also, GaAs has higher leakage than Si-this means higher dark current in the PD's and thus they aren't as sensitive on receive. These products are probably not well suited for ultra long range laser communication because practial considerations cancel out the gains provided by the decreased atmospheric attenuation. Hope this helps- GL and good dx. Art. ----- These made it through the system several days BEFORE the switch. You should have gotten copies back from the reflector... John K3PGP@juno.com http://www.qsl.net/k3pgp -==- >From owner-laser Tue Sep 2 13:58:59 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA07331; Tue, 2 Sep 97 13:58:59 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Tue, 2 Sep 1997 13:53:13 -0700 From: c1040@azfms.com (Rusty Carruth) Message-Id: <199709022053.NAA23024@fmswksn06.azfms.dot> To: laser@qth.net Subject: [LASER] ftp place? X-Sun-Charset: US-ASCII Reply-To: c1040@azfms.com (Rusty Carruth) Sender: owner-laser@berlioz.nsc.com Precedence: bulk On Tue, 2 Sep 1997 09:42:13 -0700 c1040@azfms.com (Rusty Carruth) writes: > >Hmm. What's wrong with a directory with permissions >777. Or possibly a directory with permissions that >allow writing only (lots of places call that directory >'upload'), then a cron job to periodically move >anything there that does NOT reproduce a name already >present in the destination dir, to the destination dir >for all to see. > >Did that make sense??? > >rusty > ----- You need to take this up with Al, K3TKJ. It's his system NOT mine! I'm co-sysop of the laser listserve not the system it runs on! We really could use a temporary place to stick all the data that people want to send but so far I can't seem to get anyone to fix the problem with the laser ftp directory... ----end copied message---- Ok, tell ya what - I'll volunteer my home machine (or maybe a friends home machine - I've got to talk to him first) for a dumping ground. Let me get the details worked out and I'll be back with ya... (Unless someone else wants to step in to the gap for the short term) rusty, living in Tempe AZ near n7ot! >From owner-laser Tue Sep 2 15:02:18 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA10028; Tue, 2 Sep 97 15:02:18 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Date: Tue, 2 Sep 1997 17:54:45 -0400 Subject: Re: [LASER] ftp place? Message-Id: <19970902.175449.5086.0.K3PGP@juno.com> References: <199709022053.NAA23024@fmswksn06.azfms.dot> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 0-17,19-20,23-24,26-27,29-35 From: k3pgp@juno.com (John K3PGP) Reply-To: k3pgp@juno.com (John K3PGP) Sender: owner-laser@berlioz.nsc.com Precedence: bulk >On Tue, 2 Sep 1997 09:42:13 -0700 c1040@azfms.com (Rusty Carruth) >writes: > >Ok, tell ya what - I'll volunteer my home machine >(or maybe a friends home machine - I've got to >talk to him first) for a dumping ground. > >Let me get the details worked out and I'll be back >with ya... > >(Unless someone else wants to step in to the gap >for the short term) > >rusty, living in Tempe AZ near n7ot! > ----- I appreciate the offer but we really need to get this going on qsl.net or qth.net as everything else is here including the web pages... We went through this before with stuff all over the place and I don't want to have to consolidate it again as it was very confusing for everyone concerned. I'll jog Al's memory again and see if he can resolve it now that the move to qth.net is complete. As a last resort I do maintain another internet adr. that stuff can be sent to if all else fails. John K3PGP@juno.com http://www.qsl.net/k3pgp -==- >From owner-laser Wed Sep 3 17:51:11 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA02197; Wed, 3 Sep 97 17:51:11 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <340E0481.24F4@prodigy.net> Date: Wed, 03 Sep 1997 19:44:49 -0500 From: KC5AN Organization: Prodigy Internet X-Mailer: Mozilla 3.0 (Win95; I) Mime-Version: 1.0 To: Laser Reflector Subject: [LASER] laser mcw at hf/vhf? Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Reply-To: KC5AN Sender: owner-laser@berlioz.nsc.com Precedence: bulk 1. Can a laser diode be modulated (mcw) at 140 Mhz? If not, how about 30 MHz? 2. Can a PIN or APD receiver operate at 140 MHz? If not, how about 30 MHZ? 73 john kc5an n. texas >From owner-laser Wed Sep 3 20:38:39 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA07398; Wed, 3 Sep 97 20:38:39 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Date: Wed, 3 Sep 1997 23:11:51 -0400 Subject: Re: [LASER] laser mcw at hf/vhf? Message-Id: <19970903.232124.19710.3.K3PGP@juno.com> References: <340E0481.24F4@prodigy.net> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 0-3,5-6,9-14,19-20,22-23,25-31 From: k3pgp@juno.com (John K3PGP) Reply-To: k3pgp@juno.com (John K3PGP) Sender: owner-laser@berlioz.nsc.com Precedence: bulk On Wed, 03 Sep 1997 19:44:49 -0500 KC5AN writes: >1. Can a laser diode be modulated (mcw) at 140 Mhz? > If not, how about 30 MHz? Laser diodes can be modulated up into the Ghz range! I know of a couple of commercial systems with modulation capabilities up to at least 40 Ghz! I've had a couple of systems running with a 10 Mhz passband that I used for some experimental video work. The transmitter seemed to have no problem handling higher frequencies up to at least 150 Mhz. >2. Can a PIN or APD receiver operate at 140 MHz? > If not, how about 30 MHZ? I know a PIN diode can do this. However, you will have to reverse bias it to make it respond to this high a freq. Shunt capacitance will be your biggest problem as it causes a high frequency rolloff. The sensitivity will be terrible however due to the high noise floor associated with this kind of bandwidth and the reverse bias. If you need this kind of bandwidth you may need to consider a PMT depending on the needed sensitivity. I don't have any idea on the APD as I never had one to play with. However, I would think they would behave about the same as a PIN diode. John K3PGP@juno.com http://www.qsl.net/k3pgp -==- >From owner-laser Fri Sep 5 12:31:09 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA20635; Fri, 5 Sep 97 12:31:09 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Fri, 5 Sep 97 12:23:27 PDT From: jmoss@berlioz.nsc.com (Jim Moss) Message-Id: <9709051923.AA20336@berlioz.nsc.com> To: laser@qth.net Subject: [LASER] Records Reply-To: jmoss@berlioz.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk I got a copy of the VHF+ records from Al Ward. I've put them on my website. It currently has the 474 and 678 THz records listed. (Records are based on 1/7/97 data.) webpage: http://www.qsl.net/wb9ajz/laser/laser.htm direct to records: http://www.qsl.net/wb9ajz/laser/data/vhfrec.htm There is also an Excel spreadsheet in the /laser/data directory. >From owner-laser Fri Sep 5 17:24:20 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA01001; Fri, 5 Sep 97 17:24:20 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: Date: Sat, 6 Sep 1997 00:22:26 +0100 To: laser@qth.net Cc: laser@qsl.net From: Jim Hatton Subject: [LASER] LD info ? Mime-Version: 1.0 X-Mailer: Turnpike Version 3.03 Reply-To: Jim Hatton Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi Has anyone any info on a Laser Diode from a CD player with type number 8C20 This is not the only number written on the case, the other is 0122 but I suspect that's a batch number or similar. The Diode is mounted in a can with a sloping front face. The face is about 30 deg slope. I know it's a 780nm 5mW device but that's all. Thanks in advance. Jim GM4RJX -- Jim Hatton __|__ Diana GM4RJX | 31 August 1997 | RIP >From owner-laser Sun Sep 7 09:20:58 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA01882; Sun, 7 Sep 97 09:20:58 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <01BCBB7E.692A8940@tnt2-190.HiWAAY.net> From: "Edward M. Myszka III" To: "'Laser Reflector'" Subject: [LASER] Laser diode from Sony CD player Date: Sun, 7 Sep 1997 11:10:40 -0500 Reply-To: "Edward M. Myszka III" Sender: owner-laser@berlioz.nsc.com Precedence: bulk I just pulled a laser diode from a Sony Discman CD player. On the back there are three pin connections in a triangular orientation. I have identified the ground connection and the positive power connection. There is a SMD capacitor across the grnd and power connection (filtering I assume). The third connection , what is this for? It appears to have a SMD pot across it. What sort of voltage should I power the laser diode with? Thanks, Mike >From owner-laser Sun Sep 7 14:54:05 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA10166; Sun, 7 Sep 97 14:54:05 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970907153558.007fe7e0@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Sun, 07 Sep 1997 15:35:58 -0500 To: laser@qth.net From: "Art Allen, KY1K" Subject: [LASER] EXCELLENT parts supplier! Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi Everyone, I found what has to be the greatest parts supplier in the world! OE Technologies has some good deals on pmt's. They have MANY S-20 and S-11 type (up to 850nm) extended red types, some priced as low as 55 dollars (range $55 to $195). The also have a 2 inch IR ONLY tube (500-1100nm, peak at 750nm) for 95 dollars-GREAT DEAL for those using IR laser tx's! It a 2 inch Dumont, model 6911. They have a sellout going on now, too many optical filters in stock.... 40 nm passband, various center frequencies in stock (657nm thru 900nm) center frequencies. They claim 77 percent transmittance! Size is 8 mm by 31 mm, price is $6.95 each. They DO NOT sell junk, their prices are VERY VERY fair. They quarantee satisfaction (30 day money back). They stock sockets for most of the tubes they sell, and they sell RCA, Amprex, Thorn-EMI, RCA and Hamamatsu pmt's. They sell other related optical stuff too, as well as top shelf lab equipment and test gear. This is the type of outfit that I wouldn't hesitate to buy a pmt from because these guys appear to know what the Hell they are doing-unlike some other outfits that DON'T! They have an online catalog, but I requested the hard copy. It came in the mail FAST! They have no 800 number. Voice is 505-583-2482, FAX is 505-583-9190 and they have email too (oetech@newmexico.com)!!!! I'm thinking very seriously about purchasing that IR only tube! GL and good dx...Art... >From owner-laser Sun Sep 7 18:34:45 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA15817; Sun, 7 Sep 97 18:34:45 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970907202607.008174d0@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Sun, 07 Sep 1997 20:26:07 -0500 To: laser@qth.net From: "Art Allen, KY1K" Subject: [LASER] pmt supply from batteries... Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi everyone- Here is a press release regarding new batteries available from GOULD. These are a very attractive option for anyone wishing to run a pmt directly from batteries-remember, such a scheme DOES NOT waste power in the divider resistors, so there is NO WASTED power. An added benefit is that the pmt is much easier to cool too-the typical divider string wastes 300 mw (heat) in close proxity to the tube base. So, its MUCH HARDER TO COOL a resistive divider based pmt unit. The price per battery is 4 dollars each in 500 quan-not cheap, but remember that the batteries would last a VERY VERY long time when running a pmt-they are 50 ma hours and the pmt runs less than 100ua at full output and usually less than 50 pa in no light conditions. I would jump on these myself if they were nicads or some other type of rechargable battery! Maybe technology will bring more acceptable options in the near future. Anyway, just wanted everyone to know the option for direct battery power is there for those needing extreme portability and light weight. GL..Art.... ---------------------------- Start press release... Eastlake, OH -- New from Gould Electronics Inc., Powerdex Division is what the vendor calls the world's thinnest, lightweight OEM primary battery for the PC Card industry. According to the company, these new lithium batteries are 0.6mm thick x 4cm x 3cm and provide a nominal voltage of 33V and 50 mA-hour capacity. Because of its thin prismatic format and unusual attachment feature that does not require a battery holder, the battery can be easily placed over a populated printed circuit board. For more information, contact: Gould Electronics, Inc., 35129 Curtis Blvd., Eastlake, OH 44095-4001. Tel: 216-953-5059; fax: 216-953-5152. See Us at Electro booth 72 End press release... PS-Dave, I sent the award to the person who gave me the information about the 33 v cells-I'm sure you will agree with me that it beats a string of 100 transistor batteries all to heck. No offense intended. >From owner-laser Sun Sep 7 19:46:44 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA17370; Sun, 7 Sep 97 19:46:44 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Sun, 7 Sep 1997 19:33:34 -0700 (PDT) From: Clifford Buttschardt To: "Art Allen, KY1K" Cc: laser@qth.net Subject: Re: [LASER] pmt supply from batteries... In-Reply-To: <3.0.1.32.19970907202607.008174d0@colby.edu> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Reply-To: Clifford Buttschardt Sender: owner-laser@berlioz.nsc.com Precedence: bulk I take it that three will be required between each dynode and that the total voltage will still be 1100 or so volts. Tapping each battery does seem attractive. Does this seems the way you would suggest using the newer lithium batteries? Cliff K7RR On Sun, 7 Sep 1997, Art Allen, KY1K wrote: > Hi everyone- > > Here is a press release regarding new batteries available from GOULD. > > These are a very attractive option for anyone wishing to run a pmt directly > from batteries-remember, such a scheme DOES NOT waste power in the divider > resistors, so there is NO WASTED power. > > An added benefit is that the pmt is much easier to cool too-the typical > divider string wastes 300 mw (heat) in close proxity to the tube base. So, > its MUCH HARDER TO COOL a resistive divider based pmt unit. > > The price per battery is 4 dollars each in 500 quan-not cheap, but remember > that the batteries would last a VERY VERY long time when running a pmt-they > are 50 ma hours and the pmt runs less than 100ua at full output and usually > less than 50 pa in no light conditions. > > I would jump on these myself if they were nicads or some other type of > rechargable battery! Maybe technology will bring more acceptable options in > the near future. > > Anyway, just wanted everyone to know the option for direct battery power is > there for those needing extreme portability and light weight. > > GL..Art.... > > ---------------------------- > > Start press release... > > Eastlake, OH -- New from Gould Electronics Inc., Powerdex Division is > what the vendor calls the world's thinnest, lightweight OEM primary > battery for the PC Card industry. > > According to the company, these new lithium batteries are 0.6mm > thick x 4cm x 3cm and provide a nominal voltage of 33V and 50 > mA-hour capacity. > > Because of its thin prismatic format and unusual attachment feature > that does not require a battery holder, the battery can be easily > placed over a populated printed circuit board. > > For more information, contact: Gould Electronics, Inc., 35129 > Curtis Blvd., Eastlake, OH 44095-4001. > Tel: 216-953-5059; fax: 216-953-5152. > See Us at Electro booth 72 > > > > End press release... > > > > PS-Dave, I sent the award to the person who gave me the information about > the 33 v cells-I'm sure you will agree with me that it beats a string of > 100 transistor batteries all to heck. No offense intended. > > > > >From owner-laser Sun Sep 7 23:48:24 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA23338; Sun, 7 Sep 97 23:48:24 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <2.2.16.19970908063652.3ac75ba8@personal.eunet.fi> X-Sender: oh2aue@personal.eunet.fi X-Mailer: Windows Eudora Pro Version 2.2 (16) Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Mon, 08 Sep 1997 09:36:52 +0300 To: "Art Allen, KY1K" , laser@qth.net From: Michael Fletcher Subject: Re: [LASER] pmt supply from batteries... Reply-To: Michael Fletcher Sender: owner-laser@berlioz.nsc.com Precedence: bulk Art, >According to the company, these new lithium batteries are 0.6mm >thick x 4cm x 3cm and provide a nominal voltage of 33V and 50 >mA-hour capacity. Are you sure these aren't 3.3 Volt batteries ? Michael _\\///_ _ _ _ (' O O ') (_()_()_) I.O.O.F. *------------ooO-(_)-Ooo---------------------------* * Michael Fletcher OH2AUE: 50 MHz * * Vanhaistentie 4 C 43 144 MHz * * FIN-00420 Helsinki 432 MHz * * 1296 MHz * * Phone/Fax + 358 9 566 62 63 home 2.304 GHz * * Cellular + 358 50 5505 293 3.400 GHz * * Phone + 358 9 5259 1890 work 5.760 GHz * * http://personal.eunet.fi/pp/oh2aue/ 10.368 GHz * * 24.092 GHz * * Life is above 1 GHz; 474 THz * * >99.9 % of the ham bands are there..... * *--------------------------------------------------* >From owner-laser Mon Sep 8 06:50:23 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA03447; Mon, 8 Sep 97 06:50:23 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970908084335.0080a260@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Mon, 08 Sep 1997 08:43:35 -0500 To: Michael Fletcher From: "Art Allen, KY1K" Subject: Re: [LASER] pmt supply from batteries... Cc: laser@qth.net In-Reply-To: <2.2.16.19970908063652.3ac75ba8@personal.eunet.fi> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi Michael, Good to hear from you. No, I'm not absolutely sure... But the text in the message that quoted the specs was taken directly from the web-one of their press releases! You can see it at http://www.us-tech.com/march96/prods/prodprev/elpr003.htm. I did talk to them by phone to get pricing, Im not actually sure if I discussed the voltage output tho. I think it's pretty unlikely that they would get a press release that messed up tho-that would be a major boo boo. GL and good dx. Im going to hold on for awhile and hope that this technology produces a micro cell that is rechargable. Art... At 09:36 AM 09/08/1997 +0300, you wrote: >Art, > >>According to the company, these new lithium batteries are 0.6mm >>thick x 4cm x 3cm and provide a nominal voltage of 33V and 50 >>mA-hour capacity. > >Are you sure these aren't 3.3 Volt batteries ? > >Michael > > _\\///_ _ _ _ > (' O O ') (_()_()_) I.O.O.F. > *------------ooO-(_)-Ooo---------------------------* > * Michael Fletcher OH2AUE: 50 MHz * > * Vanhaistentie 4 C 43 144 MHz * > * FIN-00420 Helsinki 432 MHz * > * 1296 MHz * > * Phone/Fax + 358 9 566 62 63 home 2.304 GHz * > * Cellular + 358 50 5505 293 3.400 GHz * > * Phone + 358 9 5259 1890 work 5.760 GHz * > * http://personal.eunet.fi/pp/oh2aue/ 10.368 GHz * > * 24.092 GHz * > * Life is above 1 GHz; 474 THz * > * >99.9 % of the ham bands are there..... * > *--------------------------------------------------* > > > >From owner-laser Mon Sep 8 07:08:18 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA03839; Mon, 8 Sep 97 07:08:18 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970908090232.007f6ca0@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Mon, 08 Sep 1997 09:02:32 -0500 To: oetech@newmexico.com From: "Art Allen, KY1K" Subject: [LASER] WOW! Cc: laser@qth.net Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hey there Donald- I just got your catalog (hard copy via snail mail). I was very impressed! I forgot to bookmark your www site, please send me the URL. Thanks. I'm interested in your 2 inch Dumont, model 6911 PMT. Are they 'pulls' or NOS? How many do you have, what's the best price you can give (including socket, preferably a bare socket without components mounted/unpotted). Also, do you have hookup info and complete specs for them? Can you give a price break for 2 or 3 quan if I am willing to coordinate a group purchase (tubes, sockets and some optical filters)? Congrats on a great concept-first rate merchandise at reasonable prices and a wonderful selection! I hope you and your people use care and don't mishandle pmt's during the equipment decomissioning process for pulls (unlike some others that sell pmt's). Thanks... Art Allen >From owner-laser Mon Sep 8 07:16:43 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA04180; Mon, 8 Sep 97 07:16:43 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970908091529.007fbc70@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Mon, 08 Sep 1997 09:15:29 -0500 To: Clifford Buttschardt From: "Art Allen, KY1K" Subject: Re: [LASER] pmt supply from batteries... Cc: laser@qth.net In-Reply-To: References: <3.0.1.32.19970907202607.008174d0@colby.edu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi Cliff, John, k3pgp, did some work earlier that suggested that pmt's actually produce better s/n ratios at around 600 to 700 volts. So, I might be tempted to stack 2 per dynode rather than 3 per dynode. The s/n ratio formula in the tech info supplied in the Hamamatsu catalog suggests the the higher the gain, the better the s/n ratio-this is contrary to John's report. But, John did the measurements and I do not dispute them. I might tap the stack at every 2nd cell or at every third cell- The saving grace in using an over sized battery in terms of electrical capacity is that they are regulated because the supply is pretty stiff-I just wish they were rechargable hi hi! GL...Art... At 07:33 PM 09/07/1997 -0700, you wrote: >I take it that three will be required between each dynode and that the >total voltage will still be 1100 or so volts. Tapping each battery does >seem attractive. Does this seems the way you would suggest using the >newer lithium batteries? Cliff K7RR > > >On Sun, 7 Sep 1997, Art Allen, KY1K wrote: > >> Hi everyone- >> >> Here is a press release regarding new batteries available from GOULD. >> >> These are a very attractive option for anyone wishing to run a pmt directly >> from batteries-remember, such a scheme DOES NOT waste power in the divider >> resistors, so there is NO WASTED power. >> >> An added benefit is that the pmt is much easier to cool too-the typical >> divider string wastes 300 mw (heat) in close proxity to the tube base. So, >> its MUCH HARDER TO COOL a resistive divider based pmt unit. >> >> The price per battery is 4 dollars each in 500 quan-not cheap, but remember >> that the batteries would last a VERY VERY long time when running a pmt-they >> are 50 ma hours and the pmt runs less than 100ua at full output and usually >> less than 50 pa in no light conditions. >> >> I would jump on these myself if they were nicads or some other type of >> rechargable battery! Maybe technology will bring more acceptable options in >> the near future. >> >> Anyway, just wanted everyone to know the option for direct battery power is >> there for those needing extreme portability and light weight. >> >> GL..Art.... >> >> ---------------------------- >> >> Start press release... >> >> Eastlake, OH -- New from Gould Electronics Inc., Powerdex Division is >> what the vendor calls the world's thinnest, lightweight OEM primary >> battery for the PC Card industry. >> >> According to the company, these new lithium batteries are 0.6mm >> thick x 4cm x 3cm and provide a nominal voltage of 33V and 50 >> mA-hour capacity. >> >> Because of its thin prismatic format and unusual attachment feature >> that does not require a battery holder, the battery can be easily >> placed over a populated printed circuit board. >> >> For more information, contact: Gould Electronics, Inc., 35129 >> Curtis Blvd., Eastlake, OH 44095-4001. >> Tel: 216-953-5059; fax: 216-953-5152. >> See Us at Electro booth 72 >> >> >> >> End press release... >> >> >> >> PS-Dave, I sent the award to the person who gave me the information about >> the 33 v cells-I'm sure you will agree with me that it beats a string of >> 100 transistor batteries all to heck. No offense intended. >> >> >> >> > > >From owner-laser Tue Sep 9 01:42:21 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA13889; Tue, 9 Sep 97 01:42:21 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Date: Tue, 9 Sep 1997 04:25:02 -0400 Subject: [LASER] PMT SNR Message-Id: <19970909.043424.14974.3.K3PGP@juno.com> References: <3.0.1.32.19970907202607.008174d0@colby.edu> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 1-13,16-17,22-23,26-32 From: k3pgp@juno.com (John K3PGP) Reply-To: k3pgp@juno.com (John K3PGP) Sender: owner-laser@berlioz.nsc.com Precedence: bulk On Mon, 08 Sep 1997 09:15:29 -0500 "Art Allen, KY1K" writes: > >John, k3pgp, did some work earlier that suggested >that pmt's actually produce better s/n ratios at >around 600 to 700 volts. So, I might be tempted >to stack 2 per dynode rather than 3 per dynode. > >The s/n ratio formula in the tech info supplied >in the Hamamatsu catalog suggests the the higher >the gain, the better the s/n ratio-this is >contrary to John's report. But, John did the >measurements and I do not dispute them. The Hamamatsu data may or may not be true for a NEW tube. This seems to go against what I've read and the reports of several other people on this list. However, if we can't trust Hamamatsu who can we trust? After testing 193 USED PMTs it became very obvious that every tube had it's own sweet spot. If the voltage was raised above this level the gain did come up but the noise came up faster meaning the resulting SNR was degraded. Best SNR was achieved at anywhere between 560 and 1175 volts for different samples of the same tube !!! If your goal is best SNR you may need to fine tune the voltage. If your goal is highest gain go for as much voltage as you can put on the tube without it arcing! John K3PGP@juno.com http://www.qsl.net/k3pgp -==- >From owner-laser Wed Sep 10 19:00:08 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA03937; Wed, 10 Sep 97 19:00:08 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <1.5.4.32.19970911015251.006f6ef0@luminet.net> X-Sender: cjeffers@luminet.net (Unverified) X-Mailer: Windows Eudora Light Version 1.5.4 (32) Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Wed, 10 Sep 1997 20:52:51 -0500 To: laser@qth.net From: Jim Jefferson Subject: [LASER] $10 Laser power supplies Reply-To: Jim Jefferson Sender: owner-laser@berlioz.nsc.com Precedence: bulk In my latest copy of All Electronics Corporation catalog (came today) there is listed: "Laser Power Supplies (USED) Used power supplies, removed fromequipment, the specs vary somewhat from one supply to another. Black epoxy case. Wire Leads. Avaible for 12VDC or 115 vac input. Includes hook-up diagram. Output, no load: 7,500 - 10,000 VDC Output, with load: 1.700 - 2,500 VDC 12 Vdc INPUT CAT # LPS-3 $10 each 115 VAC INPUT CAT # LPS-5 $10" I would type in contact information, but you can just go to www.allcorp.com ... So, are these power supplies deals? Would it be suitable for running a cheap he-ne tube? 73's de Jim Jefferson KB0THN cjeffers@luminet.net http://www.luminet.net/~cjeffers/ ps. If anybody has noticed or cared, school terminated my account (jjeffers@wms.luminet.net), so use the above address. >From owner-laser Wed Sep 10 20:57:20 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA07931; Wed, 10 Sep 97 20:57:20 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f From: Mike (N3YPA) Message-Id: <199709110352.XAA10542@techsrv1.tech.mtu.edu> Subject: [LASER] Data transfer with laser To: laser@qth.net Date: Wed, 10 Sep 1997 23:52:11 -0400 (EDT) X-Mailer: ELM [version 2.4 PL25] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Reply-To: Mike (N3YPA) Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hello, I am working on a project for my school work that deals with free space data communications using lasers. Right now it is working at a speed of up to 56k or 57kbits/s, but if we try to go faster the data on the output of the amplifier going to the schmitt trigger in the receiver becomes stretched and we either start losing bits of data or the schmitt trigger will just not switch. We are using a pin diode for detecting the light source right now with two to three stages of amplification afterwards. What kind of devices are out there that can conduct faster than a pin diode when detecting light and are more sensitive? Thanks for any help in advance. TTYL, Mike N3YPA/8 -- *-------------------------------------------------------------* * When you are content to be simply yourself * * and don't compare or compete, * * everybody will respect you. * * Tao Te Ching, by Lao-tzu * *-------------------------------------------------------------* >From owner-laser Thu Sep 11 01:13:49 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA16508; Thu, 11 Sep 97 01:13:49 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Date: Thu, 11 Sep 1997 04:07:07 -0400 Subject: [LASER] Free Email Providers ? Message-Id: <19970911.040709.15974.0.K3PGP-2@juno.com> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 2-3,8-9,16-17,20-26 From: k3pgp-2@juno.com (John x) Reply-To: k3pgp-2@juno.com (John x) Sender: owner-laser@berlioz.nsc.com Precedence: bulk I know this doesn't directly apply to lasers but I've run into a serious problem using juno.com as my Email provider and I know it's affecting other subscribers to this list as well! It seems as though juno.com implemented a new policy this week that limits the number of connections and the amount of data you can process per account in a 24 hour period. Apparently their restrictions are rather severe as I sometimes exceed that amount in one connection per day! What other Free Email providers are out there that do NOT require an internet service provider? (With juno.com you do NOT need an ISP as they have dial up numbers in most cities. However, you MUST use their software which is fine with me!) As I know there are other people on this list that are using juno.com that are now having this problem as well I thought I'd ask here and see if anyone knows of any other similar Free Email providers that do NOT require an ISP. I do maintain a backup account with an ISP but unfortunately it's on a pay as you go plan as I can't see paying $20 a month for unlimited access which I don't need! John K3PGP@juno.com http:/www.qsl.net/k3pgp -==- >From owner-laser Thu Sep 11 04:16:37 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA21170; Thu, 11 Sep 97 04:16:37 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Thu, 11 Sep 97 07:12:25 EDT From: sam@stdavids.picker.com (Sam Goldwasser) Message-Id: <9709111112.AA12025@stdavids.picker.com> To: cjeffers@luminet.net, laser@qth.net Subject: Re: [LASER] $10 Laser power supplies Reply-To: sam@stdavids.picker.com (Sam Goldwasser) Sender: owner-laser@berlioz.nsc.com Precedence: bulk Greetings: I checked the their web page. > "Laser Power Supplies (USED) > > Used power supplies, removed from equipment, the specs vary > somewhat from one supply to another. Black epoxy case. > Wire Leads. Available for 12VDC or 115 vac input. Includes > hook-up diagram. > > Output, no load: 7,500 - 10,000 VDC > Output, with load: 1.700 - 2,500 VDC > > 12 Vdc INPUT > CAT # LPS-3 $10 each > 115 VAC INPUT > CAT # LPS-5 $10" > > I would type in contact information, but you can just go to > www.allcorp.com ... > > So, are these power supplies deals? Would it be suitable for > running a cheap he-ne tube? Does it state the current? They sound like really good deals to me and would be suitable for tubes up to 2-3 mW, possibly as high as 5 mW (depending on precise specs). You would just need a ballast resistor, probably 75K. The only unknown is the current - these are typically regulated at 4-6 mA depending on model. However, you will not be able to modify these supplies in any way since they sound like they are totally potted and have no adjustments. Also, it would appear that the specs vary from unit to unit so some may be more capable (higher ned of the range) than others. Some may be too powerful for .5-1 mW tubes. Still a good deal. The cheapest I have seen supplies like these previously surplus would be in the $40 (other than internet private indiviuls). See the Laser FAQ below for more technical information. --- sam : Sci.Electronics.Repair FAQ: http://www.paranoia.com/~filipg/REPAIR/ Coming soon to a computer screen near you: http://www.repairfaq.org/ Preview of V3.00 (ASCII): http://www.pacwest.net/byron13/sammenu.htm Lasers: http://www.geocities.com/CapeCanaveral/Lab/3931/lasersam.htm (Now http://www.misty.com/~don/lasersam.html V3.0x) http://www.pacwest.net/byron13/laserfaq.htm http://www.repairfaq.org/REPAIR/F_laserfaq.html (Formatted!) > 73's de > > Jim Jefferson KB0THN > cjeffers@luminet.net > http://www.luminet.net/~cjeffers/ > > ps. If anybody has noticed or cared, school terminated my > account (jjeffers@wms.luminet.net), so use the above address. > > >From owner-laser Fri Sep 12 07:09:07 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA10923; Fri, 12 Sep 97 07:09:07 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <01BCBF63.28B8D2C0@spokes.mnsinc.com> From: Spokes To: "'laser@qth.net'" Subject: [LASER] Noise sources and power needs in PMT systems Date: Fri, 12 Sep 1997 09:41:02 -0400 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8bit X-Mime-Autoconverted: from quoted-printable to 8bit by ns3.qth.net id KAA01055 Reply-To: Spokes Sender: owner-laser@berlioz.nsc.com Precedence: bulk >30 years ago, when I was using PMT type systems it was common knowledge that almost all the noise in PMT systems was in the first stage and almost all the current demand was in the last dynode stage. I note a lot of discussion of batteries etc. If folks recognized that PMT power demand is negligible except for the last couple of dynodes it could make for even more economical design. All the signal quality care needs to be at the cathode end and all the power attention (if you call a few microamps power) needs to be at the output end. What goes on in the middle requires only routine attention. The voltages on the PMT do not have to be the same for every dynode. The minimum noise that will be achieved by a particular PMT will come about if each electron emitted from the cathode is multiplied to a sub-microsecond pulse (of e.g. ten million electrons) from the last dynode. Since the pulse is spread over a period of a few tens of nanoseconds, pulse detection can reduce noise. Ideally, when there are no photo-electrons released from the cathode there should be no current from the last dynode. If your telescope produces a tiny spot of light, in principle, a smaller cathode PMT is likely to have a smaller noise simply because noise at some level is dominated by the area of cathode. Corona from over-voltaged intermediate stages can cause problems. Perhaps all this is a little out of date and perhaps similar comments have slid past me. I do admit to not having read every word that all you fine experimenters are writing. If I have missed your inputs on these subjects, my apologies for the BW. Neil AB4YK. >From owner-laser Fri Sep 12 13:50:20 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA23504; Fri, 12 Sep 97 13:50:20 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Fri, 12 Sep 97 13:38:41 PDT From: jmoss@berlioz.nsc.com (Jim Moss) Message-Id: <9709122038.AA23049@berlioz.nsc.com> To: laser@qth.net Subject: [LASER] Non-member submission - PMT info? Reply-To: jmoss@berlioz.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk Forward: From: "Myszka, Mike" To: "'laser@qth.net'" Subject: Possible PMT Date: Fri, 12 Sep 1997 11:27:48 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.1664.3) Content-Type: text/plain I found two devices that I think may be PMT's, but I don't know since I've never worked (or seen one). The first device is made by Pacific Photometric Instruments and about 1 foot long and about 4 in. dia. There is a label on the outside of the black tube housing. It says PMT Housing, RCA-6199, model # 62-1A12. There is a opening in one end. A reflective surface can be seen. If this is a PMT, has it been damaged since that opening wasn't covered. On the other end, there are two BNC connectors. One is labeled HV, the other signal. There is also a 4 pin power connection. Finally, there is a switch with 4 settings....10K, 1K, 100K, 10M. The other device is about 6 in. long and 4 in. dia. It is from Electronic Optics Associates with the model number as PM-101-1. There is an opening, but it is covered with aluminum tape. The other end has 2 BNC connectors labeled HV and PM. There is a switch with 5 positions...0.1, 1, 10, 100K, and infinity. Can anyone h*e*l*p me ID these? If they are PMT, how can I tell if they work. I've never used a PMT, what sort of HV is used. Any help would be of use. Mike ----- End Included Message ----- >From owner-laser Fri Sep 12 16:54:45 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA01332; Fri, 12 Sep 97 16:54:45 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Fri, 12 Sep 97 16:45:55 PDT From: jmoss@berlioz.nsc.com (Jim Moss) Message-Id: <9709122345.AA00840@berlioz.nsc.com> To: laser@qth.net Subject: [LASER] Laser and 10G from MT Diablo, CA Reply-To: jmoss@berlioz.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk Subject: Laser Sat night WB9AJZ and N5XSA will be trying to operate from Mt Diablo (CM97) on laser and xband on Saturday PM. Anyone want to try it??? We will also have 6 and 2m for points and coordination. Jim >From owner-laser Sat Sep 13 09:06:51 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA27725; Sat, 13 Sep 97 09:06:51 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f From: daveaa1a@xensei.com Date: Sat, 13 Sep 1997 11:59:05 -0400 Message-Id: <199709131559.LAA21679@xensei2.xensei.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Subject: [LASER] Light Collectors To: laser@qth.net X-Mailer: SPRY Mail Version: 04.00.06.17 Reply-To: daveaa1a@xensei.com Sender: owner-laser@berlioz.nsc.com Precedence: bulk I always see the darndest stuff at yard sales like a kids 2' telescope or larger and how easy it is to mount a tv camera, laser, or photo diode at the rear.. All for usually around a buck.. Am qrv now with the yard sale originated laser transceiver.. The quest is over today... A like new small b/w tv that runs on 12vdc completes the poor mans CW/Voice/Data LAN.. Now I can finally aim the darn thing.. Am QRV from fn42/41/51.. + Hilltopping Keep America in the race.. 73s de dave - aa1a >From owner-laser Sat Sep 13 12:52:09 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA05229; Sat, 13 Sep 97 12:52:09 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <01BCC05B.FB2B3100@spokes.mnsinc.com> From: Spokes To: "'aballen@colby.edu'" Cc: "'laser@qth.net'" Subject: Re: [LASER] Noise sources and power needs in PMT systems Date: Sat, 13 Sep 1997 15:43:45 -0400 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8bit X-Mime-Autoconverted: from quoted-printable to 8bit by ns3.qth.net id PAA01847 Reply-To: Spokes Sender: owner-laser@berlioz.nsc.com Precedence: bulk Art: Here are some annotated comments on your notes: ==================================================KY1K writes: Hey Neil, I'm the one who is making all the trouble about alternative power sources for pmt's! I am about to employ a professional engineer to design a MODERN TECHNOLOGY power supply unit for me, and the project is currently on hold for lack of MY UNDERSTANDING of the current demands for the individual elements of the pmt. I did order some tech info regarding divider string design from Thorne, but it talks mainly about pulse opeartion, where tube output current is LARGE, but occasional. It does not discuss the relationship between dynode element current consumption and how it relates to plate and cathode current levels-so, that's my problem right now. =======================================AB4YK writes: Each photoelectron emitted from the cathode hits the next dynode with about 100 eV energy releasing 3 to 10 more electrons with a peak around 5 secondary electrons. Each secondary electron then travels to the next stage where it in turn releases another 3 - 10 electrons. The secondary emission is not a steep function of applied voltage. However, you want to stay away from big voltages because you get corona if the voltages are too high. 100 volts per stage works fine. After 10 dynode amplification stages, the final number of electrons associated with a single initial photoelectron can easily be calculated. It is the multiplication factor (5) raised to the tenth power -- 5^[10] or 9,765,625 - call it 10,000,000 electrons. The spread in time of these electrons arriving at the final dynode may be in the sub-ten nanosecond range (I could be off an order of magnitude) with the details depending on the dynode design and focusing of electrons from stage to stage etc. However, 10,000,000 electrons in 10 ns is a current of {1.6X10^(-19) coulombs per electronX 10^[7] electrons/1^(-8)sec} amp = 0.16 mA - but only for a very small fraction of a microsecond. Note that the last but one dynode has only one fifth of this current and the preceding one to that has only 1/25th of this amount of current. If the dynode structure (last dynode) has a stray capacity of 3 pF, then the arrival of 10^[7] electrons there will momentarily change the voltage of the capacitor [dynode] by V = Q/C or 1.6X10^[-19]X10^[7]/3X10^[-12] or 0.533 V. So each initial photoelectron produces a pulse of near mA level current but only for nanosecs and quite big voltage excursions are obtained at the last dynode for each photoelectron released. For the most part, the capacitance of the structure works well with microamp level supplies relying on the capacity of the system's structure to even out the power demand. But those huge sub-microsecond pulses are all there for the asking - a 1k resistor is just fine for developing your signal to be amplified - use 100 MHz type techniques for the signal amplification. If your final average current is 1.6X10^[-10] A after multiplication of 10^[7] then your original current is 1.6X10^[-17] amp or 100 electrons per second. You can amplify the DC or you can amplify the pulses. It's a whole lot less noisy to amplify the pulses if your light signal is very weak. In the pulse case, you are working with near milliamp signals and near-1volt potential excursions, but if you average the weak signals, you are working with fractions of nanoamps. When you have 10^[6] photoelectrons at the cathode per second, your final amplified current is getting into the microamp range and any method of amplification works. Much more than this and you will begin to have pulse collisions and the usual signal amplification methods are more appropriate. With 1,000,000 photoelectrons/s from the cathode using a pulse system, noise will be ~Sqrrt[10^6], i.e. ~ 10^3 which is ~ one part in 10^3 averaged over one second. That doesn't look too good to me, if you're looking for a data transfer rate approaching 1kb/s, so you will probably want to work at signal levels well above that so as to get away from practical! They are pricey, but rechargability would mean that they would last forever, so the initial high cost would be offset. Well (unfortunately), these cells AREN'T recehargable though! Since they are throw away once depleted, I can't justify the high cost of the initial purchease. So, I'm still looking for appropriate batteries to DIRECT POWER a PMT. GL...Art... PS-Incidently, power supply technology and pmt technology has changed little in 30 years, your tech knowledge of this topic is just as current NOW as it was 30 years ago-thanks for the information above. ===========================AB4YK writes: Usually, the cathode is at -1000 volts. At the photocathode, the current demand is minuscule (sub-pico amps). As you approach ground potential the current picks up in the dynode string to the higher levels but from batteries that are much closer to ground potential ~ 100 - 200 volts below ground potl for the last but one and last but two dynodes. The currents are as described above. The final dynode (anode) is usually, very conveniently, near ground potential so you can use simple techniques to handle the signal. Art, and others, I hope this clarifies things a bit. BTW, I'm sure you're aware of it, but others may not be so aware: If you have batteries totaling 1000 V, an electric shock from these could be lethal or lead to potentially fatal muscle spasms if taken on a structure or ladder. A fall from a few feet or stoppage of the heart for a few minutes can lead to fatal results. Personally, I have always been a bit scared of batteries with more than 50 volts output. 73, Neil, AB4YK. > > >From owner-laser Sun Sep 14 10:54:18 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA09335; Sun, 14 Sep 97 10:54:18 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <01BCC115.7A921800@spokes.mnsinc.com> From: Spokes To: "'aballen@colby.edu'" Cc: "'laser@qth.net'" Subject: Re: [LASER] Noise sources...unscrambling of last half of msg Date: Sun, 14 Sep 1997 13:52:06 -0400 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8bit X-Mime-Autoconverted: from quoted-printable to 8bit by ns3.qth.net id NAA14393 Reply-To: Spokes Sender: owner-laser@berlioz.nsc.com Precedence: bulk Art: The last half of my msg was unaccountably scrambled. Here is what I sent (last half of msg only): =================AB4YK wrote: With 1,000,000 photoelectrons/s from the cathode using a pulse system, noise will be ~Sqrrt[10^6], i.e. ~ 10^3 which is ~ one part in 10^3 averaged over one second. That doesn't look too good to me, if you're looking for a data transfer rate approaching 1kb/s, so you will probably want to work at signal levels well above that so as to get away from data that is representative of individual photoelectrons. I'll hand this part of the discussion off to the EE guys who make a living at this stuff. So the way that you are going to be operating - extreme weak signals or high data transfer rates - will decide your signal levels. That should lead you to your choice of signal handling techniques at the business end of the PMT. ===========================================Back to KY1K:============ I wonder if you can help me to understand the current relationships within the pmt? I understand dark operation-all currents equal zero (atleat in theory). But, let's say my pmt has 9 dynodes and a gain of e^6 (1,000,000). I operate each dynode and the cathode from their own separate ps units. This means 10 psu's (-100v, -200v, -300v, -400v, -500v, -600v, -700v, -800v, -900v and the business end of the tube at -1000v). When the output current is 1 ua, what are the respective dynode currents? When the output current is 10 ua, what are the respective dynode currents? When the output current is 100 ua, what are the respective dynode currents? Also, what is the relationship between the current that flows in the plate connection compared to the current that flows in the cathode for each of these cases? Does plate current equal cathode current plus the sums of all the individaul dynode currents? I am attempting to quantify the current demands of the indidual dynodes and the plate/cathode so that I can BUILD/DESIGN a modern switching supply that doesn't use resistors for achieving the dynode voltages-but the actual relationship of the current demands for the individual elements is NEVER DISCUSSED in any of the tech material I've seen. Can you help? ----------------- Incidently, regarding direct battery drive of PMT's... Clearly this is the ultimate in simplicity and a pmt would run forever on batteries (almost) as there is little wasted power. I did locate 33v 50 ma hour cells that are VERY COMPACT. So, a stack of 30 with a tap at every 3rd cell would be very practical! They are pricey, but rechargability would mean that they would last forever, so the initial high cost would be offset. Well (unfortunately), these cells AREN'T recehargable though! Since they are throw away once depleted, I can't justify the high cost of the initial purchease. So, I'm still looking for appropriate batteries to DIRECT POWER a PMT. GL...Art... PS-Incidently, power supply technology and pmt technology has changed little in 30 years, your tech knowledge of this topic is just as current NOW as it was 30 years ago-thanks for the information above. ===========================AB4YK wrote: Usually, the cathode is at -1000 volts. At the photocathode, the current demand is minuscule (sub-pico amps). As you approach ground potential the current picks up in the dynode string to the higher levels but from batteries that are much closer to ground potential ~ 100 - 200 volts below ground potl for the last but one and last but two dynodes. The currents are as described above. The final dynode (anode) is usually, very conveniently, near ground potential so you can use simple techniques to handle the signal. Art, and others, I hope this clarifies things a bit. BTW, I'm sure you're aware of it, but others may not be so aware: If you have batteries totaling 1000 V, an electric shock from these could be lethal or lead to potentially fatal muscle spasms if taken on a structure or ladder. A fall from a few feet or stoppage of the heart for a few minutes can lead to fatal results. Personally, I have always been a bit scared of batteries with more than 50 volts output. 73, Neil, AB4YK. > > >From owner-laser Tue Sep 16 18:00:20 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA18404; Tue, 16 Sep 97 18:00:20 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f From: rimshot@worldnet.att.net Message-Id: <341F45C1.13CA@worldnet.att.net> Date: Tue, 16 Sep 1997 19:51:45 -0700 X-Mailer: Mozilla 3.0C-WorldNet (Win16; I) Mime-Version: 1.0 To: laser@qth.net Subject: [LASER] Newbie asks questions Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Reply-To: rimshot@worldnet.att.net Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi Folks, I've been 'playing' with lasers on and off for about 5 years now.Im a field service rep. for a company that sells/services analytical instruments for medical labs. Having access to HeNe lasers that we replace when they get < 2mw and lots of other optical compontents,I started to look into what I could do with them.I got interested in homemade holograms,but never got as far as making them.(I hear you need a least 10mw to make good ones).Anyway,Im interested in what you guys/(gals)? are doing with free air communications. First,is it direct line of sight between laser and receiver?I did see where cloud bouncing was mentioned.Are you able to receive information from the image of the beam?I thought that the modulated light had to fall onto the detector. Where I live there are no wide open spaces,so what I've been experimenting with has been the laser window bounce receiver.I built the one from 'The Laser Cookbook'and one from Information Unlimited.Nothing sinister here, I've been using reflective material streched across needlepoint hoops and showing the kids how we can pick-up sounds/voice when they're across the field near the hoop.(try to get them interested in science,etc.)One of the receviers uses a red LED the other a phototransistor.Are the detectors you're using better for what Im doing? I saw where the Burr-Brown OPA210/211 was mentioned.I'd like to try that and see. One last question.I've used a 3x9x40 rifle scope on the detector.Contrary to what I thought would be the most sensitive position for the detector(the focal point of the eyepiece),it was further back where the laser pattern was about 1.5 inches in diameter.Has this been your experience? I hope it's OK to send this to the group.Please let me know what the correct protocol is when asking these questions.Thanks for your time. Regards, John >From owner-laser Wed Sep 17 11:52:53 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA24465; Wed, 17 Sep 97 11:52:53 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f From: daveaa1a@xensei.com Date: Wed, 17 Sep 1997 14:46:28 -0400 Message-Id: <199709171846.OAA15686@xensei2.xensei.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Subject: Re: [LASER] Newbie asks questions To: rimshot@worldnet.att.net, laser@qth.net X-Mailer: SPRY Mail Version: 04.00.06.17 Reply-To: daveaa1a@xensei.com Sender: owner-laser@berlioz.nsc.com Precedence: bulk On Tue, 16 Sep 1997, rimshot@worldnet.att.net wrote: >interested in what you guys/(gals)? are doing with free air >communications. >First,is it direct line of sight between laser and receiver?I did see >where cloud bouncing was mentioned.Are you able to receive information Hi John... Yes direct line of sight out to MANY miles is possible.. Kinda determined by atmospheric conditions and line of sight.. (Mountain tops) (Not that non-LOS doesn't work).. Check out the archives of this reflector and also K3PGP and WB9AJZ home pages.. >experimenting with has been the laser window bounce receiver.I built the >one from 'The Laser Cookbook'and one from Information Unlimited.Nothing Did you use a tone or subcarrier or just an unmodulated laser diode..??.. >One last question.I've used a 3x9x40 rifle scope on the >detector.Contrary >to what I thought would be the most sensitive position for the >detector(the focal point of the eyepiece),it was further back where the Best I've been able to find out is that the size of the light beam striking the substrate fills the active area for most signal out.. It depends on the most light.. NOT FOCUS... 73s from dave - aa1a >From owner-laser Wed Sep 17 14:26:03 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA01010; Wed, 17 Sep 97 14:26:03 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970917161914.008845f0@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Wed, 17 Sep 1997 16:19:14 -0500 To: rimshot@worldnet.att.net From: "Art Allen, KY1K" Subject: Re: [LASER] Newbie asks questions Cc: laser@qth.net In-Reply-To: <341F45C1.13CA@worldnet.att.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk At 07:51 PM 09/16/1997 -0700, you wrote: >Hi Folks, > >I've been 'playing' with lasers on and off for about 5 years now.Im a >field service rep. for a company that sells/services analytical >instruments for medical labs. > >Having access to HeNe lasers that we replace when they get < 2mw and >lots of other optical compontents,I started to look into what I could do >with them.I got interested in homemade holograms,but never got as far as >making them.(I hear you need a least 10mw to make good ones).Anyway,Im >interested in what you guys/(gals)? are doing with free air >communications. > >First,is it direct line of sight between laser and receiver?I did see >where cloud bouncing was mentioned.Are you able to receive information >from the image of the beam?I thought that the modulated light had to >fall >onto the detector. Hi John, In cloud bounce, the modulated light bounces off the cloud and is reflected back to a receiver. So, light DOES have to fall on a detector. Note that you can 'talk to yourself' using cloud bounce! If you are careful to limit your own receiver and transmitter fields of view, you can leave the transmitter running while listening to the rx, and you won't hear anything until the laser actually hits a cloud or airplane or other object. You can also hear your own signals by bouncing your tx signal off of distant trees, buildings, towers etc. You can talk to other people using this method too. I think a couple of the users here have worked line of sight at 90 miles using lasers, there is no reason why you couldn't do the same. You can work the longest line of sight paths with inexpensive gear and a modest sized light collector. KB1RP and K3PGP are investigating the feasability of working non line of sight paths (random atmospheric reflections). This takes a higher power transmitter, a larger lens to collect light for the receiver and a very sensitive receiver (pm tube or APD) for best results-lesser setups don't make it when ultraweak signals are involved. KB1RP has conventional DSP capability via his computer sound card... K3PGP uses high tech digital processing and BPSK techniques. So the experimenters run loose here, literally, reaching for the stars. first time I heard someone mention non-line of sight contacts, I thought they must have been partaking of controlled substances-now I realize I was the one who was all wet. > >Where I live there are no wide open spaces, Where do you live? Finding someone else to talk to can be tough on laser, make your location known to us, someone else on the list might be looking for a fellow experimenter in their area. >so what I've been >experimenting with has been the laser window bounce receiver.I built the >one from 'The Laser Cookbook'and one from Information Unlimited.Nothing >sinister here, I've been using reflective material streched across >needlepoint hoops and showing the kids how we can pick-up sounds/voice >when they're across the field near the hoop.(try to get them interested >in science,etc.)One of the receviers uses a red LED the other a >phototransistor.Are the detectors you're using better for what Im doing? >I saw where the Burr-Brown OPA210/211 was mentioned.I'd like to try that >and see. > Try the opa210/211 !!!! They aren't quite as good as a full blown descrete amp/photodiode, but they are within a few db in terms of weak signal reception is concerned. The opa210 will run circles around your LED or phototransistor receivers and they are easy to build and they are cheap! Be sure to shield them, and don't try to run too much gain, stick to the BB specs for feedback resistor values. For HE-NE wavelengths, a PMT is the ultimate in receiver sensitivity-esp'ly if you can find a red enhanced unit. PMT's are no picnic to handle, they take special care and operate at high voltage. If you need the extreeme sensitivity, they are the way to go for HE-NE. Otherewise, stick to photodiode and solid state electronic type detectors. Your lab equipment doesn't use red enhanced pmt's by any chance, does it? >One last question.I've used a 3x9x40 rifle scope on the >detector.Contrary >to what I thought would be the most sensitive position for the >detector(the focal point of the eyepiece),it was further back where the >laser pattern was about 1.5 inches in diameter.Has this been your >experience? > OK, you got me on this one.... >I hope it's OK to send this to the group.Please let me know what the >correct protocol is when asking these questions.Thanks for your time. > Protocol is loose-very loose. Ask- Better yet, how about detailing your results of the window bounce receiver? Be sure to check out k3pgp's web site, there is a massive ammount of info there. Good luck, and happy experimenting. Welcome to the group. Art in Freedom, ME. >From owner-laser Wed Sep 17 18:39:13 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA12472; Wed, 17 Sep 97 18:39:13 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Subject: [LASER] Introduction. Message-Id: <19970916.212229.5351.2.corbettgriffith@juno.com> References: <3.0.1.32.19970917161914.008845f0@colby.edu> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 4-5,11-14,16 From: corbettgriffith@juno.com (Corbett Griffith) Date: Wed, 17 Sep 1997 21:26:08 EDT Reply-To: corbettgriffith@juno.com (Corbett Griffith) Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hello, I am Corbett Griffith and I am a Senior at Parkview High School in Lilburn, Georgia (near Atlanta). For my Independent Study project at school, I chose to build a He-Ne laser system. I have got the Laser Cookbook and Sam Goldwasser's Laser FAQ. The Laser FAQ is the best resource I have yet to find. I have not began building my laser as I am still in the research phase. As of now, I plan to use a 5 mw tube and a home built power supply from Sam's FAQ. If any of you have any advice on how to not kill myself (with High Voltages) or on laser techniques, I would show much appreciation. Anyone know of a local (Atlanta) Surplus Outlet with laser stuff or neeto electronics junk? Thanks, CorbettGriffith@Juno.com "Timid men prefer the calm despotism to the tempestuous sea of liberty" -Thomas Jefferson >From owner-laser Thu Sep 18 05:35:54 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA03115; Thu, 18 Sep 97 05:35:54 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Thu, 18 Sep 97 08:31:34 EDT From: sam@stdavids.picker.com (Sam Goldwasser) Message-Id: <9709181231.AA14294@stdavids.picker.com> To: corbettgriffith@juno.com, laser@qth.net Subject: Re: [LASER] Introduction. Reply-To: sam@stdavids.picker.com (Sam Goldwasser) Sender: owner-laser@berlioz.nsc.com Precedence: bulk Greetings: As mentioned on this forum, All Electronics is currently selling surplus HeNe laser power supplies for $10. This is an unbeatable deal if they have not all been grabbed up by now. If you can convince them to select one of those at the higher end of the specs they list, it *may* drive a 5 mW tube = certainly 2 or 3 mW: http://www.allcorp.com/graphics/pdf/88-4.pdf. Then, all you need is possibly a ballast resistor and input components (line cord/switch/fuse/indicator or 12 V power supply depending on type). As far as general electronic HV safety, see the "Notes on Safety...." document referred to in the FAQ. Laser safetly is covered briefly in the FAQ with references to laser safety related web sites. At 5 mW, it is mostly common sense - never look into the (collimated) beam or direct the laser in such a way that someone else (inside or outside) could accidentally do so. The graveyard joke goes something like: "Never stare into the beam with your remaining good eye." --- sam : Sci.Electronics.Repair FAQ: http://www.paranoia.com/~filipg/REPAIR/ Coming soon to a computer screen near you: http://www.repairfaq.org/ Preview of V3.00 (ASCII): http://www.pacwest.net/byron13/sammenu.htm Lasers: http://www.geocities.com/CapeCanaveral/Lab/3931/lasersam.htm (Now http://www.misty.com/~don/lasersam.html V3.0x) http://www.pacwest.net/byron13/laserfaq.htm http://www.repairfaq.org/REPAIR/F_laserfaq.html (Formatted!) > Hello, I am Corbett Griffith and I am a Senior at Parkview High School in > Lilburn, Georgia (near Atlanta). For my Independent Study project at > school, I chose to build a He-Ne laser system. I have got the Laser > Cookbook and Sam Goldwasser's Laser FAQ. The Laser FAQ is the best > resource I have yet to find. > > I have not began building my laser as I am still in the research phase. > As of now, I plan to use a 5 mw tube and a home built power supply from > Sam's FAQ. If any of you have any advice on how to not kill myself (with > High Voltages) or on laser techniques, I would show much appreciation. > Anyone know of a local (Atlanta) Surplus Outlet with laser stuff or neeto > electronics junk? > > Thanks, > CorbettGriffith@Juno.com > "Timid men prefer the calm despotism to the tempestuous sea of liberty" > -Thomas Jefferson > >From owner-laser Thu Sep 18 06:50:29 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA05048; Thu, 18 Sep 97 06:50:29 PDT Message-Id: <34206F60.49F53BB@qsl.net> Date: Wed, 17 Sep 1997 20:01:36 -0400 From: "al@qsl.net" Organization: http://www.qsl.net X-Mailer: Mozilla 3.01Gold (X11; I; Linux 2.0.28 i486) Mime-Version: 1.0 To: listusers@qsl.net Cc: k7on@qsl.net, k3tkj@qsl.net Subject: QTH.Net Digests and Archives (for subscribers) References: <3.0.3.32.19970916025104.0109235c@mailhost.primenet.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-laser@berlioz.nsc.com Precedence: bulk This is information from K7ON, Brian for all users of reflectors at QTH.NET 73, Al, K3TKJ ----- QTH.Net Digests and Archives (for subscribers) What about Digests and Archives? Below are examples for the 'FooBar' list. You can substitute any valid QTH.Net list name for 'FooBar' (it is a dummy place holder). A. Digests All lists at QTH.Net have digests available. You can subscribe to a digest and periodically receive the compiled messages rather than individual messages. All list digests are configured for a size limit of 40,000 bytes. However, most of the files are around 16k to 30k. This is because majordomo will NOT send a digest larger than the limit. If a new message pushes beyond the limit, it sends the accumulated, putting the new message in the NEXT digest. To subscribe to a digest, subscribe to listname-digest also or instead. If you are switching from non-digest to digest, you must unsubscribe listname and subscribe listname-digest. It is an entirely seperate subscription, but both digest and non-digest subscribers are permitted to post to the non-digest list. Here is an example for the FooBar List: TO: majordomo@qth.net SUBJECT: BODY: subscribe FooBar-digest unsubscribe FooBar B. Archives All messages sent via reflector are archived and are available for access through majordomo. You can send a command to majordomo@qth.net and in the body type: index FooBar-digest and get a list of files that are available by request. Here is an example: >>>> index FooBar-digest total 116 -rw-rw---- 1 majordom 45 14169 Sep 2 18:09 v01.n042 -rw-rw---- 1 majordom 45 18100 Sep 3 11:27 v01.n043 -rw-rw---- 1 majordom 45 15322 Sep 4 14:11 v01.n044 -rw-rw---- 1 majordom 45 13490 Sep 6 11:15 v01.n045 -rw-rw---- 1 majordom 45 16382 Sep 9 18:39 v01.n046 -rw-rw---- 1 majordom 45 14823 Sep 11 08:40 v01.n047 -rw-rw---- 1 majordom 45 16872 Sep 12 01:04 v01.n048 To retrieve one of these files, send an email to majordomo@qth.net. In the body of the message, type: get FooBar-digest v01.n048 The file will be emailed to you, automagically! ----- 73, Brian >From owner-laser Thu Sep 18 19:14:00 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA03152; Thu, 18 Sep 97 19:14:00 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: sam@stdavids.picker.com Cc: laser@qth.net Subject: Re: [LASER] Introduction. Message-Id: <19970917.220040.5351.5.corbettgriffith@juno.com> References: <9709181231.AA14294@stdavids.picker.com> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 0-3,11-12,17-18,24-28,30 From: corbettgriffith@juno.com (Corbett Griffith) Date: Thu, 18 Sep 1997 22:04:13 EDT Reply-To: corbettgriffith@juno.com (Corbett Griffith) Sender: owner-laser@berlioz.nsc.com Precedence: bulk >As mentioned on this forum, All Electronics is currently selling surplus >HeNe laser power supplies for $10. This is an unbeatable deal if they >have not all been grabbed up by now. Yes, this is a great deal, but I really want to build the PSU. It is more of a learning experience, I think, to build the power supply. This would also force me to recognize the potential dangers as a real threat, not to say that I don't recognize the danger! (No safety lectures pls, I know better). Actually, I got one of those epoxy brick power supplies from a friend. It can drive 5 ma at 2100 volts. This would be fun for smaller tubes. Still, I do want to build at least a 5mw he-ne laser with my own home brew power supply. Someone mentioned buying a simple laser pointer instead. What fun is that? I want a neeto glowing, lasing, firey death tube! A diode seems too simple. There is just something magical about shooting thousands of volts through two simple gasses and creating light. I want to experience this for myself. I recently got an Information Unlimited catalog. Is this a reputable company? I guess what I am asking, has anyone had experience dealing with them and their products? All of the stuff in there looks really neat! I wish I had a couple of thousand dollars for a decent rail gun. I'd mount it in my garage and finally get some acceleration out of my Volvo Stationwagon! Thanks, Later, CorbettGriffith@Juno.com "Timid men prefer the calm despotism to the tempestuous sea of liberty" -Thomas Jefferson >From owner-laser Fri Sep 19 04:02:14 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA14930; Fri, 19 Sep 97 04:02:14 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Fri, 19 Sep 97 06:56:01 EDT From: sam@stdavids.picker.com (Sam Goldwasser) Message-Id: <9709191056.AA19128@stdavids.picker.com> To: corbettgriffith@juno.com, sam@stdavids.picker.com Subject: Re: [LASER] Introduction. Cc: laser@qth.net Reply-To: sam@stdavids.picker.com (Sam Goldwasser) Sender: owner-laser@berlioz.nsc.com Precedence: bulk > >As mentioned on this forum, All Electronics is currently selling surplus > >HeNe laser power supplies for $10. This is an unbeatable deal if they > >have not all been grabbed up by now. > > Yes, this is a great deal, but I really want to build the PSU. It is more > of a learning experience, I think, to build the power supply. This would > also force me to recognize the potential dangers as a real threat, not to > say that I don't recognize the danger! (No safety lectures pls, I know > better). Actually, I got one of those epoxy brick power supplies from a > friend. It can drive 5 ma at 2100 volts. This would be fun for smaller > tubes. Still, I do want to build at least a 5mw he-ne laser with my own > home brew power supply. Fair enough. One cannot argue with the desire to experiment and learn! > Someone mentioned buying a simple laser pointer instead. What fun is > that? I want a neeto glowing, lasing, firey death tube! A diode seems too > simple. There is just something magical about shooting thousands of volts > through two simple gasses and creating light. I want to experience this > for myself. I agree that buying a laser pointer is boring. Also, while some people claim to have trivially modified them for communications purposes, this is not true of many and it is all too easy to blow the laser diodes. > I recently got an Information Unlimited catalog. Is this a reputable > company? I guess what I am asking, has anyone had experience dealing with > them and their products? All of the stuff in there looks really neat! I > wish I had a couple of thousand dollars for a decent rail gun. I'd mount > it in my garage and finally get some acceleration out of my Volvo > Stationwagon! I don't have any first hand experience with them. However, you know what they say about "If it sounds too good to be true...." Some of their stuff may be of that category. Personally, I consider IU as a resource of what might be possible but probably would only buy specific components from them (like caps or transformers) that were not available elsewhere. I welcome opposing points of view :-). It is worth getting the Iannini books from the library (see the FAQ) as they are interesting reading. --- sam : Sci.Electronics.Repair FAQ: http://www.paranoia.com/~filipg/REPAIR/ Coming soon to a computer screen near you: http://www.repairfaq.org/ Preview of V3.00 (ASCII): http://www.pacwest.net/byron13/sammenu.htm Lasers: http://www.geocities.com/CapeCanaveral/Lab/3931/lasersam.htm (Now http://www.misty.com/~don/lasersam.html V3.0x) http://www.pacwest.net/byron13/laserfaq.htm http://www.repairfaq.org/REPAIR/F_laserfaq.html (Formatted!) > > Thanks, > Later, > CorbettGriffith@Juno.com > "Timid men prefer the calm despotism to the tempestuous sea of liberty" > -Thomas Jefferson > >From owner-laser Fri Sep 19 13:34:50 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA04748; Fri, 19 Sep 97 13:34:50 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Fri, 19 Sep 97 13:25:35 PDT From: jmoss@berlioz.nsc.com (Jim Moss) Message-Id: <9709192025.AA04449@berlioz.nsc.com> To: laser@qth.net Subject: [LASER] 30mW 780nM LD's Reply-To: jmoss@berlioz.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk Found some old Maxtor MO drives... they have Sharp LT024MD diodes in them... rated 30mW max... typical operation is at 20mW... Looks like there is a driver cct built into a board that will require simple DC supply for CW operation. in the drive are 4 pin diodes (no markings) and optics for splitting and collumnation. Not to mention some really nice mechanics to allow sliding of the "head lens". It takes about 1/2 hour to dig these pieces out.. Anyone interested? I can get the drives for $10 each. (they weigh a lot) Jim N9JIM CM87xi Sunnyvale, CA ex WB9AJZ >From owner-laser Fri Sep 19 21:23:04 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA21082; Fri, 19 Sep 97 21:23:04 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f From: rimshot@worldnet.att.net Message-Id: <34235573.308C@worldnet.att.net> Date: Fri, 19 Sep 1997 21:47:47 -0700 X-Mailer: Mozilla 3.0C-WorldNet (Win16; I) Mime-Version: 1.0 To: "Art Allen, KY1K" Cc: laser@qth.net Subject: Re: [LASER] Newbie asks questions References: <3.0.1.32.19970917161914.008845f0@colby.edu> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Reply-To: rimshot@worldnet.att.net Sender: owner-laser@berlioz.nsc.com Precedence: bulk Art Allen, KY1K wrote: > > At 07:51 PM 09/16/1997 -0700, you wrote: > >Hi Folks, > > > >I've been 'playing' with lasers on and off for about 5 years now.Im a > >field service rep. for a company that sells/services analytical > >instruments for medical labs. > >is it direct line of sight between laser and receiver?I did see > >where cloud bouncing was mentioned.Are you able to receive information > >from the image of the beam?I thought that the modulated light had to > >fall > >onto the detector. > > Hi John, > > In cloud bounce, the modulated light bounces off the cloud and is reflected > back to a receiver. So, light DOES have to fall on a detector. Note that > you can 'talk to yourself' using cloud bounce! If you are careful to limit > your own receiver and transmitter fields of view, you can leave the > transmitter running while listening to the rx, and you won't hear anything > until the laser actually hits a cloud or airplane or other object. > > You can also hear your own signals by bouncing your tx signal off of > distant trees, buildings, towers etc. You can talk to other people using > this method too. > > I think a couple of the users here have worked line of sight at 90 miles > using lasers, there is no reason why you couldn't do the same. You can work > the longest line of sight paths with inexpensive gear and a modest sized > light collector. > > KB1RP and K3PGP are investigating the feasability of working non line of > sight paths (random atmospheric reflections). This takes a higher power > transmitter, a larger lens to collect light for the receiver and a very > sensitive receiver (pm tube or APD) for best results-lesser setups don't > make it when ultraweak signals are involved. KB1RP has conventional DSP > capability via his computer sound card... K3PGP uses high tech digital > processing and BPSK techniques. > > So the experimenters run loose here, literally, reaching for the stars. > first time I heard someone mention non-line of sight contacts, I thought > they must have been partaking of controlled substances-now I realize I was > the one who was all wet. > > > > >Where I live there are no wide open spaces, > > Where do you live? Finding someone else to talk to can be tough on laser, > make your location known to us, someone else on the list might be looking > for a fellow experimenter in their area. > > >so what I've been > >experimenting with has been the laser window bounce receiver.I built the > >one from 'The Laser Cookbook'and one from Information Unlimited.Nothing > >sinister here, I've been using reflective material streched across > >needlepoint hoops and showing the kids how we can pick-up sounds/voice > >when they're across the field near the hoop.(try to get them interested > >in science,etc.)One of the receviers uses a red LED the other a > >phototransistor.Are the detectors you're using better for what Im doing? > >I saw where the Burr-Brown OPA210/211 was mentioned.I'd like to try that > >and see. > > > > Try the opa210/211 !!!! They aren't quite as good as a full blown descrete > amp/photodiode, but they are within a few db in terms of weak signal > reception is concerned. The opa210 will run circles around your LED or > phototransistor receivers and they are easy to build and they are cheap! > > Be sure to shield them, and don't try to run too much gain, stick to the BB > specs for feedback resistor values. > > For HE-NE wavelengths, a PMT is the ultimate in receiver sensitivity-esp'ly > if you can find a red enhanced unit. PMT's are no picnic to handle, they > take special care and operate at high voltage. If you need the extreeme > sensitivity, they are the way to go for HE-NE. Otherewise, stick to > photodiode and solid state electronic type detectors. > > Your lab equipment doesn't use red enhanced pmt's by any chance, does it? > > >One last question.I've used a 3x9x40 rifle scope on the > >detector.Contrary > >to what I thought would be the most sensitive position for the > >detector(the focal point of the eyepiece),it was further back where the > >laser pattern was about 1.5 inches in diameter.Has this been your > >experience? > > > > OK, you got me on this one.... > > >I hope it's OK to send this to the group.Please let me know what the > >correct protocol is when asking these questions.Thanks for your time. > > > > Protocol is loose-very loose. Ask- > > Better yet, how about detailing your results of the window bounce receiver? > > Be sure to check out k3pgp's web site, there is a massive ammount of info > there. > > Good luck, and happy experimenting. Welcome to the group. > > Art in Freedom, ME. Hi, Thanks for responding to my questions Art.Im very happy to be a part of this group!And I look forward to sharing and gathering info.on a really cool hobby. I guess Im still not clear on a few things,but before I start asking questions again,I'll answer yours first. I live in Baton Rouge,La. I have a good friend who is big into ham radio and amateur video broadcasting.Im sure he could be talked into laser comm.if there's noone else around. The instruments I work on don't use PMTs,but I looked through my 'stuff' and I found one from an older system.Don't know if it works or not.If any one's interested-let me know. About the focus of the scope and detector-I guess I wasn't specific.The light pattern returning from the vibrating membrane,gathered by the scope,diverges from the eyepiece.I thought that the most sensitive place for the detector would at the point where the pattern was smallest- focused.But no,it's farther back.It's a clear LED so I guess the 'dome' on it acts like a lense. The laser window bounce didn't work very well for me,but I believe it can work.I tried it on my den window with the TV turned up.Mostly I heard noise(externally generated and from the amp).I did pick-up the faint sound of the TV.The unit from Info.Unlimited uses a phototrans.peak response approx.950nm and 4 transistors instead of ICs in the Laser Cookbook.I asked a private investagator what techniques are used.Basically;infared for discretion,expensive DSP gear,the power of the laser and sensitivity of the receiver are important,also he said the beam should hit the center of the window and be about a foot in diameter on the window.You can also target on certain things in the room if the window is open.Conventional electronic techniques can recover signal 30db below noise levels,specialized equipment-60db below,military/intelligence using sophisticated computers-110db below. Not on my budget! Also CW and a high coherence laser. I will have to send you a second e-mail to ask my questions.I have plenty and have to go right now.Thanks again.I'll catch you later. John >From owner-laser Fri Sep 19 23:56:48 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA25422; Fri, 19 Sep 97 23:56:48 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Wed, 3 Sep 97 08:46:22 PDT From: jmoss@berlioz.nsc.com (Jim Moss) Message-Id: <9709031546.AA12651@berlioz.nsc.com> To: laser@qth.net Subject: [LASER] Archive files updated Reply-To: jmoss@berlioz.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk I've uploaded the July and August archives, and updated the membership lists on my laser website. Also updated the "Jim's laser links" with additional finds from over the last couple months. http://www.qsl.net/wb9ajz/laser/laser.htm Jim WB9AJZ/6 >From owner-laser Sat Sep 20 12:13:51 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA14787; Sat, 20 Sep 97 12:13:51 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Sat, 20 Sep 97 09:12:47 PDT From: jmoss@berlioz.nsc.com (Jim Moss) Message-Id: <9709201612.AA10653@berlioz.nsc.com> To: laser@qth.net Subject: [LASER] MO drives Reply-To: jmoss@berlioz.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk I bought 20 drives, we can get more if needed. Almost all the parts are salvagable. The only difficult part is getting a couple of the optical splitters out (they are glued in). I got them out using a pliers coated with plastic tape (like pulling teeth). Those here in the bay area should call and come pickup. Those who responded needing shipment, I am going to the Post Office this AM to get a cost for shipment. The 780nM spot is quite visible off a white wall. The beam shape and divergence looks "good". There is somewhat of an eliptical pattern, not circular. Jim N9JIM CM87xi Sunnyvale, CA ex-WB9AJZ >From owner-laser Sat Sep 20 12:15:26 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA14874; Sat, 20 Sep 97 12:15:26 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Content-Return: allowed Date: Sat, 20 Sep 1997 12:58:38 -0500 From: "Hancock, Mike" Subject: [LASER] 5mW lasers To: "'LASER'" Message-Id: Mime-Version: 1.0 X-Mailer: Internet Mail Service (5.0.1457.3) Content-Type: multipart/mixed; boundary="---- =_NextPart_000_01BCC5C4.EB114250" X-Priority: 3 X-Ms-Tnef-Correlator: Reply-To: "Hancock, Mike" Sender: owner-laser@berlioz.nsc.com Precedence: bulk This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. ------ =_NextPart_000_01BCC5C4.EB114250 Content-Type: text/plain I have several 5mW lasers. The tubes were made by Hughes, they are 10" long, and have plastic end caps. The power supply was made by Sweda, is un-enclosed, and runs on 115v ac. They are $20+postage. 73 de Mike N5LHM ------ =_NextPart_000_01BCC5C4.EB114250 Content-Type: application/ms-tnef Content-Transfer-Encoding: base64 eJ8+IikRAQaQCAAEAAAAAAABAAEAAQeQBgAIAAAA5AQAAAAAAADoAAEIgAcAGAAAAElQTS5NaWNy b3NvZnQgTWFpbC5Ob3RlADEIAQWAAwAOAAAAzQcJABQADAA6ACYABgBjAQEggAMADgAAAM0HCQAU AAwAOgAmAAYAYwEBCYABACEAAAA2NUUyQTY1NTNBMzFEMTExOEU0QTAwMDBGODYwMDk5NwDhBgEE gAEACwAAADVtVyBsYXNlcnMAowMBDYAEAAIAAAACAAIAAQOQBgCkBAAAIAAAAAMAJgAAAAAAAwA2 AAAAAAACAQkQAQAAADABAAAsAQAAsAEAAExaRnVLj43y/wAKAQ8CFQKkA+QF6wKDAFATA1QCAGNo CsBzZXTuMgYABsMCgzIDxgcTAoD+fQqACM8J2QKACoENsQtgwG5nMTAzMwr7EvIRAdAgSSARwHZl IAsR8BhgcgdAIDVtVw4gC2AR8BHgLiBUaNEYcHR1YgeRdwSQGHADAMANsCBieSBIdfJnGeBzLBoA GeAbIArA2xhwFqAiGUACIGcboABwBmQYNAtRc3RpYyAjCfAdEGNhcBmlcG+zGnEYgHVwC1AbIHcZ YGUat1MacGRhG6AEACBodW4tCfBjFGAR8GQ9HNRyIRAEIAIgHEAxNVp2HABjGbMb9CQB0CvDHuAd sGFnZS4KhQqFiDczIBrhTWlrGHDgTjVMSE0kjAqFE/ECACfwHgBwAAEAAAALAAAANW1XIGxhc2Vy cwAAAgFxAAEAAAAWAAAAAbzGB/IsBZZMmjG2EdG0N0RFU1QAAAAAQAA5ALwOd9LuxbwBAwDxPwkE AAAeADFAAQAAAAkAAABNSEFOQ09DSwAAAAADABpAAAAAAB4AMEABAAAACQAAAE1IQU5DT0NLAAAA AAMAGUAAAAAAAwD9P+QEAAACAUcAAQAAADEAAABjPVVTO2E9IDtwPVVUTUI7bD1FWENIQU5HRTEt OTcwOTIwMTc1ODM4Wi0xODk3MTgAAAAAAgH5PwEAAABHAAAAAAAAANynQMjAQhAatLkIACsv4YIB AAAAAAAAAC9PPVVUTUIvT1U9RU1BSUwvQ049UkVDSVBJRU5UUy9DTj1NSEFOQ09DSwAAHgD4PwEA AAAOAAAASGFuY29jaywgTWlrZQAAAB4AOEABAAAACQAAAE1IQU5DT0NLAAAAAAIB+z8BAAAARwAA AAAAAADcp0DIwEIQGrS5CAArL+GCAQAAAAAAAAAvTz1VVE1CL09VPUVNQUlML0NOPVJFQ0lQSUVO VFMvQ049TUhBTkNPQ0sAAB4A+j8BAAAADgAAAEhhbmNvY2ssIE1pa2UAAAAeADlAAQAAAAkAAABN SEFOQ09DSwAAAABAAAcwvA530u7FvAFAAAgwOm630u7FvAEeAD0AAQAAAAEAAAAAAAAAHgAdDgEA AAALAAAANW1XIGxhc2VycwAAHgA1EAEAAAA4AAAAPERFRjEyOEU5REFDQkQwMTE4RTQ0MDAwMEY4 NjAwOTk3NjkzQzFDQGVtYWlsLnV0bWIuZWR1PgALACkAAAAAAAsAIwAAAAAAAwAGEMsEhBMDAAcQ qwAAAAMAEBAAAAAAAwAREAAAAAAeAAgQAQAAAGUAAABJSEFWRVNFVkVSQUw1TVdMQVNFUlNUSEVU VUJFU1dFUkVNQURFQllIVUdIRVMsVEhFWUFSRTEwIkxPTkcsQU5ESEFWRVBMQVNUSUNFTkRDQVBT VEhFUE9XRVJTVVBQTFlXQVNNAAAAAAIBfwABAAAAOAAAADxERUYxMjhFOURBQ0JEMDExOEU0NDAw MDBGODYwMDk5NzY5M0MxQ0BlbWFpbC51dG1iLmVkdT4AwQ8= ------ =_NextPart_000_01BCC5C4.EB114250-- >From owner-laser Sat Sep 20 12:22:58 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA15116; Sat, 20 Sep 97 12:22:58 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970920094945.007f8570@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Sat, 20 Sep 1997 09:49:45 -0500 To: rimshot@worldnet.att.net From: "Art Allen, KY1K" Subject: Re: [LASER] Newbie asks questions Cc: laser@qth.net In-Reply-To: <34235573.308C@worldnet.att.net> References: <3.0.1.32.19970917161914.008845f0@colby.edu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk >The instruments I work on don't use PMTs, but I looked through my 'stuff' >and I found one from an older system. Don't know if it works or not. If >any one's interested-let me know. > Do you have a manufacturers type number or model number for the pmt? The green/yellow pmts are cheap and common. Red and IR types is what the group really needs. What type is your junk box unit? >About the focus of the scope and detector-I guess I wasn't specific.The >light pattern returning from the vibrating membrane,gathered by the >scope,diverges from the eyepiece.I thought that the most sensitive >place for the detector would at the point where the pattern was >smallest-focused.But no,it's farther back.It's a clear LED so I guess >the 'dome' on it acts like a lense. > The dome DOES act as a lens! If you use it in conjunction with an additional lens, the light will focus in front of the active area of the LED, and you have a problem. You can minimize this effect by placing the led at the point where the diameter of the collected light is about the same diameter as the led. It is still a very poor compromise. If you want to stick with an led receiver, you can grind the lens off using a coarse file. Take off just enough plastic to make the front surface flat for a 1/8 of an inch-just a slight nip will do it. Then you can polish the ground surface on a sheet of glass using AJAX/water for the coarse polishing. Once that looks smooth, you can do fine polishing using toothpase/water and the glass sheet. Don't use the clear gel types, they don't have fine abrasive in them. Once you get that front surface clear and shiney, you can then use your rifle scope to gather light and it will work better. Note that the sensitivity of the receiver will be degraded if you use it without an external lens for gathering light tho-thats because the built in lens of the led is no longer able to concentrate as much light. You can also use this method with phototransistors in led type packages-same principles apply. Note that a phototransistor has a very very very small active area, and that precision optics is necessary to focus ALL the received light on such a small area. This is a BIG consideration, and it's why we don't use phototransistors for long haul work. With an inexpensive phototransistor and single 741 op amps, a receiver is sensitive enough to be heard at 1 km (2 mw HE-ne tx). I also think your laser window bounce demo system would work way better if you had a more sensitive receiver. I strongly suggest that you get a burr-brown photodiode/amp integrated assembly! It has a fairly large active area and can be used at moderate distances without any lens at all, and at longer distance/bounce paths with moderate sized lens. They are probably 100 (or more) times as sensitive than the best phototransistor. Experimenter grade 1 inch lens are almost free, and 4 inch fairly high quality glass lens are 10 dollars. For serious distance, get a 12 inch by 12 inch fresnel lens for 20 bucks. hey John, GO FOR IT! And good luck...Art... >The laser window bounce didn't work very well for me,but I believe it >can >work.I tried it on my den window with the TV turned up.Mostly I heard >noise(externally generated and from the amp).I did pick-up the faint >sound of the TV.The unit from Info.Unlimited uses a phototrans.peak >response approx.950nm and 4 transistors instead of ICs in the Laser >Cookbook.I asked a private investagator what techniques are >used.Basically;infared for discretion,expensive DSP gear,the power of >the laser and sensitivity of the receiver are important,also he said the >beam >should hit the center of the window and be about a foot in diameter on >the window.You can also target on certain things in the room if the >window is open.Conventional electronic techniques can recover signal >30db >below noise levels,specialized equipment-60db >below,military/intelligence >using sophisticated computers-110db below. Not on my budget! Also CW and >a high coherence laser. > >From owner-laser Sat Sep 20 12:23:55 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA15149; Sat, 20 Sep 97 12:23:55 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Content-Return: allowed Date: Sat, 20 Sep 1997 10:17:08 -0500 From: "Hancock, Mike" To: "'LASER'" Message-Id: Mime-Version: 1.0 X-Mailer: Internet Mail Service (5.0.1457.3) Content-Type: multipart/mixed; boundary="---- =_NextPart_000_01BCC5AE.5C3E4F20" X-Priority: 3 X-Ms-Tnef-Correlator: Reply-To: "Hancock, Mike" Sender: owner-laser@berlioz.nsc.com Precedence: bulk This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. ------ =_NextPart_000_01BCC5AE.5C3E4F20 Content-Type: text/plain Hi folks, I have several 5mW HeNe tubes lasers with power supplies $20+postage. Mike N5LHM ------ =_NextPart_000_01BCC5AE.5C3E4F20 Content-Type: application/ms-tnef Content-Transfer-Encoding: base64 eJ8+Ig0PAQaQCAAEAAAAAAABAAEAAQeQBgAIAAAA5AQAAAAAAADoAAEIgAcAGAAAAElQTS5NaWNy b3NvZnQgTWFpbC5Ob3RlADEIAQWAAwAOAAAAzQcJABQACgARAAgABgAaAQEggAMADgAAAM0HCQAU AAoAEQAJAAYAGwEBCYABACEAAAA4QURFQTY1NTNBMzFEMTExOEU0QTAwMDBGODYwMDk5NwABBwEE gAEAAQAAAAAAAAENgAQAAgAAAAIAAgABA5AGABgEAAAgAAAAAwAmAAAAAAADADYAAAAAAAIBCRAB AAAAzQAAAMkAAABDAQAATFpGddvuJ+3/AAoBDwIVAqQD5AXrAoMAUBMDVAIAY2gKwHNldO4yBgAG wwKDMgPGBxMCgP59CoAIzwnZAoAKgQ2xC2DAbmcxMDMzCvsS8iEB0CBIaSACEGxrTHMsCoUKhUkg EcB2LGUgEfAZ0HIHQCA1KG1XIBgQZQfAIHS8dWIHkQtgEfAR4CAD8MB0aCBwb3cEkBnwXHVwC1AI kAQgJAHQK0UcQHMBkGdlLhi8TQRpaxngTjVMSE0vGLwasAqFE/EAISAAAAAeAHAAAQAAAAEAAAAA AAAAAgFxAAEAAAAWAAAAAbzF8WK1ZGxC2zGgEdG0N0RFU1QAAAAAQAA5AJ+SJEPYxbwBAwDxPwkE AAAeADFAAQAAAAkAAABNSEFOQ09DSwAAAAADABpAAAAAAB4AMEABAAAACQAAAE1IQU5DT0NLAAAA AAMAGUAAAAAAAwD9P+QEAAACAUcAAQAAADEAAABjPVVTO2E9IDtwPVVUTUI7bD1FWENIQU5HRTEt OTcwOTIwMTUxNzA4Wi0xODk2MzUAAAAAAgH5PwEAAABHAAAAAAAAANynQMjAQhAatLkIACsv4YIB AAAAAAAAAC9PPVVUTUIvT1U9RU1BSUwvQ049UkVDSVBJRU5UUy9DTj1NSEFOQ09DSwAAHgD4PwEA AAAOAAAASGFuY29jaywgTWlrZQAAAB4AOEABAAAACQAAAE1IQU5DT0NLAAAAAAIB+z8BAAAARwAA AAAAAADcp0DIwEIQGrS5CAArL+GCAQAAAAAAAAAvTz1VVE1CL09VPUVNQUlML0NOPVJFQ0lQSUVO VFMvQ049TUhBTkNPQ0sAAB4A+j8BAAAADgAAAEhhbmNvY2ssIE1pa2UAAAAeADlAAQAAAAkAAABN SEFOQ09DSwAAAABAAAcwcmEjQ9jFvAFAAAgwr/CDQ9jFvAEeAD0AAQAAAAEAAAAAAAAAHgAdDgEA AAABAAAAAAAAAB4ANRABAAAAOAAAADxERUYxMjhFOURBQ0JEMDExOEU0NDAwMDBGODYwMDk5NzY5 M0MxNkBlbWFpbC51dG1iLmVkdT4ACwApAAAAAAALACMAAAAAAAMABhDrXkIEAwAHEEsAAAADABAQ AAAAAAMAERAAAAAAHgAIEAEAAABMAAAASElGT0xLUyxJSEFWRVNFVkVSQUw1TVdIRU5FVFVCRVNM QVNFUlNXSVRIUE9XRVJTVVBQTElFUyQyMCtQT1NUQUdFTUlLRU41TEhNAAIBfwABAAAAOAAAADxE RUYxMjhFOURBQ0JEMDExOEU0NDAwMDBGODYwMDk5NzY5M0MxNkBlbWFpbC51dG1iLmVkdT4Ae+I= ------ =_NextPart_000_01BCC5AE.5C3E4F20-- >From owner-laser Sat Sep 20 19:34:06 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA26798; Sat, 20 Sep 97 19:34:06 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f From: rimshot@worldnet.att.net Message-Id: <3424A1F3.1272@worldnet.att.net> Date: Sat, 20 Sep 1997 21:26:27 -0700 X-Mailer: Mozilla 3.0C-WorldNet (Win16; I) Mime-Version: 1.0 To: aballen@colby.edu Cc: laser@qth.net Subject: [LASER] Questions on laser communication Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Reply-To: rimshot@worldnet.att.net Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi Art, I guess what's puzzling me most about the non-line of sight communication is...what happen to The Law of Reflection?(angle of incidence equal to angle of reflection).If in cloud bounce your talking about complete overcast,OK I can see that.But a single cloud or other object,how do you know where your beam is going to wind up? And then,if you bounce off a tree or other diffuse object,the beam is going to be diverging,scattered, and weak,right?Also I thought the surfaces had to be refective. Now Im not doubting that you guys are doing this,but Im just trying to reconcile the basic optics theory I had read.I also had to ask about laser radar on the newsgroups before...a car,moving on a bumpy road, curved surfaces,beam divergance...I got some answers which helped me realize out it works. I'll try the opa210 or 211. Which configuration on the spec.sheet would you suggest?By shielding them do you mean metal project boxes for the entire circuit? The PMT I have is a RCA 1P21 the other number on it is 85-48. I asked in the sci.electronic components newsgroup for info.on it. Hope I haven't pestered you too badly.I do appreciate your taking the time to help me out here. Thanks, John >From owner-laser Sat Sep 20 21:10:37 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA29894; Sat, 20 Sep 97 21:10:37 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Subject: [LASER] Drat! Message-Id: <19970920.000243.5351.0.corbettgriffith@juno.com> References: <3424A1F3.1272@worldnet.att.net> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 1-4,6 From: corbettgriffith@juno.com (Corbett Griffith) Date: Sun, 21 Sep 1997 00:05:33 EDT Reply-To: corbettgriffith@juno.com (Corbett Griffith) Sender: owner-laser@berlioz.nsc.com Precedence: bulk It seems that Juno ate some of my e-mail! I now don't know which of you was offering the 5 mw He-Ne's for $20 bucks, Please refresh my memory. Later, CorbettGriffith@Juno.com "Timid men prefer the calm despotism to the tempestuous sea of liberty" -Thomas Jefferson >From owner-laser Sat Sep 20 22:54:41 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA03096; Sat, 20 Sep 97 22:54:41 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Mon, 8 Sep 97 09:09:47 PDT From: jmoss@berlioz.nsc.com (Jim Moss) Message-Id: <9709081609.AA07472@berlioz.nsc.com> To: laser@qth.net Subject: [LASER] LD pinouts Reply-To: jmoss@berlioz.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk There are 3 leads, as there are actually 2 devices in the LD. the LD itself and a PIN sensor. The one with the pot attached is likely the sensor. Jim WB9AJZ >From owner-laser Sun Sep 21 01:19:01 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA07092; Sun, 21 Sep 97 01:19:01 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Date: Tue, 2 Sep 1997 14:28:55 -0400 Subject: [LASER] A Low Noise PIN diode Laser Receiver ! v1.0 b Message-Id: <19970902.142857.3638.0.K3PGP@juno.com> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 1-11 From: k3pgp@juno.com (John K3PGP) Reply-To: k3pgp@juno.com (John K3PGP) Sender: owner-laser@berlioz.nsc.com Precedence: bulk A couple of minor errors have been fixed and some additional comments posted to: * A Low Noise PIN diode Laser Receiver ! v1.0 b available on the web site posted below. John K3PGP@juno.com http://www.qsl.net/k3pgp -==- >From owner-laser Sun Sep 21 04:29:11 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA11884; Sun, 21 Sep 97 04:29:11 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Sun, 21 Sep 97 07:25:01 EDT From: sam@stdavids.picker.com (Sam Goldwasser) Message-Id: <9709211125.AA27244@stdavids.picker.com> To: jmoss@berlioz.nsc.com, laser@qth.net Subject: Re: [LASER] LD pinouts Reply-To: sam@stdavids.picker.com (Sam Goldwasser) Sender: owner-laser@berlioz.nsc.com Precedence: bulk > There are 3 leads, as there are actually 2 devices in the LD. > the LD itself and a PIN sensor. The one with the pot attached is likely the > sensor. > Jim > WB9AJZ Greetings: See the Laser FAQ at the sites below. Specifically: http://www.geocities.com/CapeCanaveral/Lab/3931/laserdio.htm --- sam : Sci.Electronics.Repair FAQ: http://www.paranoia.com/~filipg/REPAIR/ Coming soon to a computer screen near you: http://www.repairfaq.org/ Preview of V3.00 (ASCII): http://www.pacwest.net/byron13/sammenu.htm Lasers: http://www.geocities.com/CapeCanaveral/Lab/3931/lasersam.htm (Now http://www.misty.com/~don/lasersam.html V3.0x) http://www.pacwest.net/byron13/laserfaq.htm http://www.repairfaq.org/REPAIR/F_laserfaq.html (Formatted!) >From owner-laser Sun Sep 21 06:14:54 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA14274; Sun, 21 Sep 97 06:14:54 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970921081004.00810100@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Sun, 21 Sep 1997 08:10:04 -0500 To: sam@stdavids.picker.com (Sam Goldwasser) From: "Art Allen, KY1K" Subject: Re: [LASER] LD pinouts Cc: laser@qth.net In-Reply-To: <9709211125.AA27244@stdavids.picker.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk Spec's for all currently manufactured laser diodes are available on the web, check out the multitude of info @ www.thorlabs.com keep dem lasers lit and keep reaching for the sky... Art... At 07:25 AM 09/21/1997 EDT, you wrote: >> There are 3 leads, as there are actually 2 devices in the LD. >> the LD itself and a PIN sensor. The one with the pot attached is likely the >> sensor. >> Jim >> WB9AJZ > >Greetings: > >See the Laser FAQ at the sites below. Specifically: > >http://www.geocities.com/CapeCanaveral/Lab/3931/laserdio.htm > >--- sam : Sci.Electronics.Repair FAQ: http://www.paranoia.com/~filipg/REPAIR/ > Coming soon to a computer screen near you: http://www.repairfaq.org/ > Preview of V3.00 (ASCII): http://www.pacwest.net/byron13/sammenu.htm > > Lasers: http://www.geocities.com/CapeCanaveral/Lab/3931/lasersam.htm > (Now http://www.misty.com/~don/lasersam.html > V3.0x) http://www.pacwest.net/byron13/laserfaq.htm > http://www.repairfaq.org/REPAIR/F_laserfaq.html (Formatted!) > > >From owner-laser Sun Sep 21 10:05:25 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA20778; Sun, 21 Sep 97 10:05:25 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970912111924.008143f0@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Fri, 12 Sep 1997 11:19:24 -0500 To: Spokes From: "Art Allen, KY1K" Subject: Re: [LASER] Noise sources and power needs in PMT systems Cc: laser@qth.net In-Reply-To: <01BCBF63.28B8D2C0@spokes.mnsinc.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk At 09:41 AM 09/12/1997 -0400, you wrote: >>30 years ago, when I was using PMT type systems it was common knowledge that >>almost all the noise in PMT systems was in the first stage and almost all the >>current demand was in the last dynode stage. I note a lot of discussion of >>batteries etc. If folks recognized that PMT power demand is negligible except >>for the last couple of dynodes it could make for even more economical design. >>All the signal quality care needs to be at the cathode end and all the power >>attention (if you call a few microamps power) needs to be at the output end. >>What goes on in the middle requires only routine attention. The voltages on >>the PMT do not have to be the same for every dynode. >> >>The minimum noise that will be achieved by a particular PMT will come about if >>each electron emitted from the cathode is multiplied to a sub-microsecond pulse >>(of e.g. ten million electrons) from the last dynode. Since the pulse is spread >>over a period of a few tens of nanoseconds, pulse detection can reduce noise. >> >>Ideally, when there are no photo-electrons released from the cathode there should >>be no current from the last dynode. If your telescope produces a tiny spot >>of light, in principle, a smaller cathode PMT is likely to have a smaller noise >>simply because noise at some level is dominated by the area of cathode. Corona >>from over-voltaged intermediate stages can cause problems. >> >>Perhaps all this is a little out of date and perhaps similar comments have >>slid past me. I do admit to not having read every word that all you fine >>experimenters are writing. If I have missed your inputs on these subjects, my >>apologies for the BW. >> >>Neil AB4YK. >> Hey Neil, I'm the one who is making all the trouble about alternative power sources for pmt's! I am about to employ a professional engineer to design a MODERN TECHNOLOGY power supply unit for me, and the project is currently on hold for lack of MY UNDERSTANDING of the current demands for the individual elements of the pmt. I did order some tech info regarding divider string design from Thorne, but it talks mainly about pulse opeartion, where tube output current is LARGE, but occasional. It does not discuss the relationship between dynode element current consumption and how it relates to plate and cathode current levels-so, that's my problem right now. I wonder if you can help me to undersand the current relationships within the pmt? I understand dark operation-all curents equal zero (atleat in theory). But, let's say my pmt has 9 dynodes and a gain of e^6 (1,000,000). I operate each dynode and the cathode from their own separate ps units. This means 10 psu's (-100v, -200v, -300v, -400v, -500v, -600v, -700v, -800v, -900v and the business end of the tube at -1000v). When the output current is 1 ua, what are the respective dynode currents? When the output current is 10 ua, what are the respective dynode currents? When the output current is 100 ua, what are the respective dynode currents? Also, what is the relationship between the current that flows in the plate connection compared to the current that flows in the cathode for each of these cases? Does plate current equal cathode current plus the sums of all the individaul dynode currents? I am attempting to quantify the current demands of the indidual dynodes and the plate/cathode so that I can BUILD/DESIGN a modern switching supply that doesn't use resistors for achieving the dynode voltages-but the actual relationship of the current demands for the individual elements is NEVER DISCUSSED in any of the tech material I've seen. Can you help? ----------------- Incidently, regarding direct battery drive of PMT's... Clearly this is the ultimate in simplicity and a pmt would run forever on batteries (almost) as there is little wasted power. I did locate 33v 50 ma hour cells that are VERY COMPACT. So, a stack of 30 with a tap at every 3rd cell would be very practical! They are pricey, but rechargability would mean that they would last forever, so the initial high cost would be offset. Well (unfortunately), these cells AREN'T recehargable though! Since they are throw away once depleted, I can't justify the high cost of the initial purchease. So, I'm still looking for appropriate batteries to DIRECT POWER a PMT. GL...Art... PS-Incidently, power supply technology and pmt technology has changed little in 30 years, your tech knowledge of this topic is just as current NOW as it was 30 years ago-thanks for the information above. > > >From owner-laser Sun Sep 21 18:33:43 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA06525; Sun, 21 Sep 97 18:33:43 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f To: laser@qth.net Subject: [LASER] BFBF Message-Id: <19970920.212448.5351.30.corbettgriffith@juno.com> References: <3424A1F3.1272@worldnet.att.net> X-Mailer: Juno 1.38 X-Juno-Line-Breaks: 3-6,8 From: corbettgriffith@juno.com (Corbett Griffith) Date: Sun, 21 Sep 1997 21:27:41 EDT Reply-To: corbettgriffith@juno.com (Corbett Griffith) Sender: owner-laser@berlioz.nsc.com Precedence: bulk As you may know or not, BFBF stands for Big F***ing (insert favorite 'F' word) Blue Flame. Just wondering if this would result if you put a DMM in line with a laser PSU/tube solely for testing current. A friend said don't do it as it would fry the meter. Anyone care to share? Later, CorbettGriffith@Juno.com "Timid men prefer the calm despotism to the tempestuous sea of liberty" -Thomas Jefferson >From owner-laser Sun Sep 21 20:07:48 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA09644; Sun, 21 Sep 97 20:07:48 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970921220158.0082b390@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Sun, 21 Sep 1997 22:01:58 -0500 To: corbettgriffith@juno.com (Corbett Griffith) From: "Art Allen, KY1K" Subject: Re: [LASER] BFBF Cc: laser@qth.net In-Reply-To: <19970920.212448.5351.30.corbettgriffith@juno.com> References: <3424A1F3.1272@worldnet.att.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk At 09:27 PM 09/21/1997 EDT, you wrote: >As you may know or not, BFBF stands for Big F***ing (insert favorite 'F' >word) Blue Flame. Just wondering if this would result if you put a DMM in >line with a laser PSU/tube solely for testing current. A friend said >don't do it as it would fry the meter. Anyone care to share? > >Later, >CorbettGriffith@Juno.com >"Timid men prefer the calm despotism to the tempestuous sea of liberty" >-Thomas Jefferson > > Hey Corbett, I'm assuming you meant a HE-NE laser:-) Don't worry about the meter too much, think of your life FIRST. The meter is replacable, death is forever. This is a safety issue! You need to make sure the meter is rated to withstand 1.5 to 6 kv (depending on the power of the tube). 2 Things can go wrong if you use a meter that isn't rated for the voltage. 1-the meter will arc internally because the range switch and resistors that set the full scale reading are not rated for the voltage. 2-the meter chasis itself will become 'hot'. If the meter doesn't self destruct (and it probably won't), you have to be concerned with high voltage potental appearing in the chasis of the meter and the meter switch/test leads, remember, that meter is floating, so the chasis can become 'hot'. If you must use a dmm for measuring current in a HE-NE tube, make sure you put the meter in the grounded lead of the tube, not on the hv side! Some PSU's don't have a ground side, both the + and - outputs float-so there is no way to put the meter in the ground lead! Ground lead current measuring might not even save you, becasue you can get some nasty transients as the tube starts due to the current inrush from the striking voltage. Set the meter on the 10 ma scale, connect the meter and step back before turning the power on. Don't touch the meter chasis or the insulators on the test leads (they aren't rated for HV). Read ther current from a distance away. My advice is DON'T do it. Use the proper test gear or get by without measuring the current-if in doubt, increase the value of the current limiting resistor in small steps until the tube won't lite, then back up a couple of steps. No real need to measure the current at all, even if you are attempting to use an 'unknown' power supply on a different tube than it was originally designed for. Measuring voltage is easier, high voltage probes are available for dmm's that have the proper voltage isolation, they aren't so cheap tho. If you need to measure current, BUILD YOUR OWN ammeter. 10 ma is adequate, buy a meter at a swap meet. Build it in a metal box with ceramic standoffs and ground the chasis. Buy high voltage cable (7 mm solid core spark plug wire is rated 15 kv) for the test leads and run them into the box with HV connectors, or solder them directly inside the box (feed through the side of the box with gromets). You can get solid core spark plug wire from you local high performance engine shop/ race motor builder (Moroso brand and others). GL- Art... >From owner-laser Mon Sep 22 03:25:51 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA23572; Mon, 22 Sep 97 03:25:51 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Mon, 22 Sep 97 06:21:04 EDT From: sam@stdavids.picker.com (Sam Goldwasser) Message-Id: <9709221021.AA29919@stdavids.picker.com> To: corbettgriffith@juno.com, laser@qth.net Subject: Re: [LASER] BFBF Reply-To: sam@stdavids.picker.com (Sam Goldwasser) Sender: owner-laser@berlioz.nsc.com Precedence: bulk > As you may know or not, BFBF stands for Big F***ing (insert favorite 'F' > word) Blue Flame. Just wondering if this would result if you put a DMM in > line with a laser PSU/tube solely for testing current. A friend said > don't do it as it would fry the meter. Anyone care to share? Greetings: I routinely use a meter in the cathode return of HeNe laser tubes of all sizes for this purpose. See the FAQ for other comments on measuring voltage and current in these situations. I do not use a DMM around high voltages based on (other peopele's) past experience and some peculiar behavior I have observed but the analog meters do not seem to mind at all. --- sam : Sci.Electronics.Repair FAQ: http://www.paranoia.com/~filipg/REPAIR/ Coming soon to a computer screen near you: http://www.repairfaq.org/ Preview of V3.00 (ASCII): http://www.pacwest.net/byron13/sammenu.htm Lasers: http://www.geocities.com/CapeCanaveral/Lab/3931/lasersam.htm (Now http://www.misty.com/~don/lasersam.html V3.0x) http://www.pacwest.net/byron13/laserfaq.htm http://www.repairfaq.org/REPAIR/F_laserfaq.html (Formatted!) > > Later, > CorbettGriffith@Juno.com > "Timid men prefer the calm despotism to the tempestuous sea of liberty" > -Thomas Jefferson > >From owner-laser Mon Sep 22 04:14:43 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA24451; Mon, 22 Sep 97 04:14:43 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Mon, 22 Sep 97 07:11:02 EDT From: sam@stdavids.picker.com (Sam Goldwasser) Message-Id: <9709221111.AA00153@stdavids.picker.com> To: aballen@colby.edu, laser@qth.net Subject: Re: [LASER] BFBF Reply-To: sam@stdavids.picker.com (Sam Goldwasser) Sender: owner-laser@berlioz.nsc.com Precedence: bulk > At 09:27 PM 09/21/1997 EDT, you wrote: > >As you may know or not, BFBF stands for Big F***ing (insert favorite 'F' > >word) Blue Flame. Just wondering if this would result if you put a DMM in > >line with a laser PSU/tube solely for testing current. A friend said > >don't do it as it would fry the meter. Anyone care to share? > > > >CorbettGriffith@Juno.com > > Hey Corbett, > > I'm assuming you meant a HE-NE laser:-) > > Don't worry about the meter too much, think of your life FIRST. The meter > is replacable, death is forever. This is a safety issue! > > You need to make sure the meter is rated to withstand 1.5 to 6 kv > (depending on the power of the tube). 2 Things can go wrong if you use a > meter that isn't rated for the voltage. > > 1-the meter will arc internally because the range switch and resistors that > set the full scale reading are not rated for the voltage. Greetings: Actually worse than this if in the positive side - the starting voltage can be up to 15 KV or more - and it may be a pulse. > 2-the meter chasis itself will become 'hot'. If the meter doesn't self > destruct (and it probably won't), you have to be concerned with high > voltage potental appearing in the chasis of the meter and the meter > switch/test leads, remember, that meter is floating, so the chasis can > become 'hot'. > If you must use a dmm for measuring current in a HE-NE tube, make sure you > put the meter in the grounded lead of the tube, not on the hv side! Some > PSU's don't have a ground side, both the + and - outputs float-so there is > no way to put the meter in the ground lead! If at all possible, the power supply should be set up so that the negative is earth/safety grounded. Just think of what would happen if you connected one of those nifty aluminum laser heads to your PS! > Ground lead current measuring might not even save you, becasue you can get > some nasty transients as the tube starts due to the current inrush from the > striking voltage. There will be about 10-20X running current momentary transient as the starting circuit capacitance discharges through the tube limited by the ballast resistor. Of course, stray capacitance can increase this even more. An analog meter probably won't care since the energy is very low but a DMM could be damaged. > Set the meter on the 10 ma scale, connect the meter and step back before > turning the power on. Don't touch the meter chasis or the insulators on the > test leads (they aren't rated for HV). Read ther current from a distance away. > > My advice is DON'T do it. For a DMM. I wouldn't go that far for a VOM or just a 10 mA meter movement. > Use the proper test gear or get by without measuring the current-if in > doubt, increase the value of the current limiting resistor in small steps > until the tube won't lite, then back up a couple of steps. No real need to > measure the current at all, even if you are attempting to use an 'unknown' > power supply on a different tube than it was originally designed for. This may be easier said than done if you are using a homemade power supply where the output is adjustable and you need to be able to drive multiple HeNe tubes (but not at the same time :-) ). Then, you will want to be able to monitor current all the time. > Measuring voltage is easier, high voltage probes are available for dmm's > that have the proper voltage isolation, they aren't so cheap tho. Well, that depends. If the HV probe impedance is too low, it will load down the starting circuit. I put my meter at the input to the starting circuit so this is not an issue. Then, you just need to be able to handle the running voltage (1-5 KV) unless the supply is one of those wide compliance types where the starting circuit really isn't entirely separate. Thus, I prefer to measure current. > If you need to measure current, BUILD YOUR OWN ammeter. 10 ma is adequate, > buy a meter at a swap meet. Build it in a metal box with ceramic standoffs > and ground the chasis. Buy high voltage cable (7 mm solid core spark plug > wire is rated 15 kv) for the test leads and run them into the box with HV > connectors, or solder them directly inside the box (feed through the side > of the box with gromets). You can get solid core spark plug wire from you > local high performance engine shop/ race motor builder (Moroso brand and > others). Or a TV repair shop (or an old TV). The fat (usually red) wire to the CRT will be rated 40 KV or so. Note: spark plug wire may have a resistive core and this will probably not work. Such a meter is best. It also doesn't tie up your expensive Fluke. All my power supplies (homemade) have banana jacks for just such a current meter (across a 1K resistor). Then, you can use either a 0-10V voltmeter (1 V/mA) or a 0-10 mA ammeter. And, removing the meter doesn't interrupt the tube circuit. For more info, see the FAQ. --- sam : Lasers: http://www.geocities.com/CapeCanaveral/Lab/3931/lasersam.htm (Now http://www.misty.com/~don/lasersam.html V3.0x) http://www.pacwest.net/byron13/laserfaq.htm http://www.repairfaq.org/REPAIR/F_laserfaq.html (Formatted!) > > GL- > > Art... > > > > > >From owner-laser Mon Sep 22 09:25:51 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA04646; Mon, 22 Sep 97 09:25:51 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970922105242.00894c40@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Mon, 22 Sep 1997 10:52:42 -0500 To: sam@stdavids.picker.com (Sam Goldwasser) From: "Art Allen, KY1K" Subject: Re: [LASER] BFBF Cc: laser@qth.net In-Reply-To: <9709221111.AA00153@stdavids.picker.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk > >> Buy high voltage cable (7 mm solid core spark plug >> wire is rated 15 kv). You can get solid core spark plug wire from your >> local high performance engine shop/race motor builder (Moroso brand and >> others). > >Or a TV repair shop (or an old TV). The fat (usually red) wire to the CRT >will be rated 40 KV or so. Note: spark plug wire may have a resistive core >and this will probably not work. > NOT ALL SPARK PLUG WIRE IS 'RESISTIVE'!!!! Please note:the 'solid core' spark plug wire I referred to in my original post IS NOT resistive, it's 24 GA solid metallic wire surrounded by HV insulation. Both 7 and 8 mm sizes are available in a metallic conductor and a carbon impregnated string (resistive) type. Make sure you get the solid wire center conductor type. I mention Speed Shops and High Performance engine builders as a source because the spark plug wires on your street car is the WRONG TYPE and you local auto supply place will probably NOT have the solid core stuff. It should be noted that the 7 and 8 mm solid core wire is MASIVE OVERKILL for HE-NE laser tube voltages-better to be running higher quality insulation when your life is at stake. The automotive spark plug cable has the added benefit of being rated for HIGH TEMP and is tough as nails-very abrasion resistant. If anyone is building an amp with a remotely located power supply over 2 kv, they should be using this type of cable to carry the HV! GL.. Art... >From owner-laser Mon Sep 22 09:26:24 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA04665; Mon, 22 Sep 97 09:26:24 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <3.0.1.32.19970922105418.0088e690@colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 3.0.1 (32) Date: Mon, 22 Sep 1997 10:54:18 -0500 To: laser@qth.net From: "Art Allen, KY1K" Subject: [LASER] APD's? Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: "Art Allen, KY1K" Sender: owner-laser@berlioz.nsc.com Precedence: bulk Is anyone on the group using APD's? I've just completed an evaluation of them (pre-purchase type), and would like to report my findings to the group. If anyone is actually using them, please contact me via P mail. GL... Art... >From owner-laser Mon Sep 22 16:54:19 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA18959; Mon, 22 Sep 97 16:54:19 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Mon, 22 Sep 97 10:57:20 PDT From: jmoss@berlioz.nsc.com (Jim Moss) Message-Id: <9709221757.AA07893@berlioz.nsc.com> To: laser@qth.net Subject: RE: [LASER] BFBF Reply-To: jmoss@berlioz.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk ----- Begin Included Message ----- >From postmaster@ns3.qth.net Mon Sep 22 08:03:28 1997 From: Mark Pipes To: owner-laser Subject: RE: [LASER] BFBF Date: Mon, 22 Sep 97 07:55:00 PDT Encoding: 26 TEXT X-Mailer: Microsoft Mail V3.0 Content-Length: 788 if you want to measure the tube current, measure the VOLTAGE across the ballast resistor (1k ohms?) and use Ohm's law. 1K will yield 1 volt/ma, 10 K will yield 10 V/ ma, 1 meg yields 1 v /ua, etc. This is method my supply uses. 73 Mark KB7RJF ---------- From: owner-laser[SMTP:owner-laser@ns3.qth.net] Sent: Sunday, September 21, 1997 9:27 PM To: laser Subject: [LASER] BFBF As you may know or not, BFBF stands for Big F***ing (insert favorite 'F' word) Blue Flame. Just wondering if this would result if you put a DMM in line with a laser PSU/tube solely for testing current. A friend said don't do it as it would fry the meter. Anyone care to share? Later, CorbettGriffith@Juno.com "Timid men prefer the calm despotism to the tempestuous sea of liberty" -Thomas Jefferson ----- End Included Message ----- >From owner-laser Mon Sep 22 17:34:02 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA20551; Mon, 22 Sep 97 17:34:02 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Mon, 22 Sep 97 20:25:08 EDT From: sam@stdavids.picker.com (Sam Goldwasser) Message-Id: <9709230025.AA03305@stdavids.picker.com> To: jmoss@berlioz.nsc.com, laser@qth.net Subject: RE: [LASER] BFBF Reply-To: sam@stdavids.picker.com (Sam Goldwasser) Sender: owner-laser@berlioz.nsc.com Precedence: bulk RE: measuring HeNe tube current. > From: Mark Pipes > > if you want to measure the tube current, measure the VOLTAGE across the > ballast resistor (1k ohms?) and use Ohm's law. 1K will yield 1 volt/ma, > 10 K will yield 10 V/ ma, 1 meg yields 1 v /ua, etc. This is method my > supply uses. > 73 > Mark > KB7RJF Unless this is built into the supply, I prefer not to use any approach which measures current in the anode lead as for most implementations, this will have the operating and starting votages on it whereas the cathode end of the tube is usually at ground potential (or should be if at all possible). Inserting a current meter at this point is relatively low risk. But, an analog VOM or simple panel meter is more robust than a DMM. See my other email on this subject or the FAQ. --- sam Lasers: http://www.geocities.com/CapeCanaveral/Lab/3931/lasersam.htm (Now http://www.misty.com/~don/lasersam.html V3.0x) http://www.pacwest.net/byron13/laserfaq.htm http://www.repairfaq.org/REPAIR/F_laserfaq.html (Formatted!) >From owner-laser Mon Sep 22 18:20:48 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA22301; Mon, 22 Sep 97 18:20:48 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <342716E8.78D4@prodigy.net> Date: Mon, 22 Sep 1997 20:10:00 -0500 From: KC5AN Organization: Prodigy Internet X-Mailer: Mozilla 3.0 (Win95; I) Mime-Version: 1.0 To: Laser Reflector Subject: [LASER] Roster by location Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Reply-To: KC5AN Sender: owner-laser@berlioz.nsc.com Precedence: bulk For those of us who might want to sked & meet for QSO, I would like to establish a roster, by location. I will (and believe me--- I rarely volunteer for ANYTHING) keep and maintain a list of active laser operators, sorted by state (or country, for our non-U.S. fellow fanatics), if there is enough response to show that others car about having the same information. All needed is your on-air name, your callsign (if you are a ham), your city & state, and your gridsquare. You can post them here, or to my personnal e-mail at kc5an@prodigy.net If there is good response, I will post the results in about a week. If not, I will abandon the project. Meanwile, let me start it: KC5AN JOHN Near Dallas TX EM12 >From owner-laser Mon Sep 22 19:37:14 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA24705; Mon, 22 Sep 97 19:37:14 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f From: n7stu@psnw.com Message-Id: <3.0.1.16.19970922192042.08877e70@mail.psnw.com> X-Sender: n7stu@mail.psnw.com X-Mailer: Windows Eudora Light Version 3.0.1 (16) Date: Mon, 22 Sep 1997 19:20:42 To: laser@qth.net Subject: [LASER] FWD: Laser Contact Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Reply-To: n7stu@psnw.com Sender: owner-laser@berlioz.nsc.com Precedence: bulk I don't know if Harold is on this reflector or not but I didn't see it here and knew it would be of interest. >Return-Path: owner-wswss@ns3.qth.net >X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-wswss@qth.net using -f >Date: Mon, 22 Sep 1997 19:13:25 -0700 >From: Harold Sibert >To: wswss@qth.net >Subject: [WSWSS] Laser Contact >Sender: owner-wswss@qth.net >Reply-To: Harold Sibert > >WB7VVD and KC7AED make 119.6 mile HeNe laser contact. >By Harold Sibert KC7AED > >Sunday 9/21/97 a group of us set out to see if we could make a 119 mile >laser contact. We had already made several 20 and 30 mile contacts, >then found an optical path of 119 miles between Four Peaks, East of >Phoenix, and Smith Peak, West of Wickenburg AZ. Greg N7VUB and I >(KC7AED) went to Four Peaks in DM 43, Ward WB7VVD and Adam KC7PCV went >to Smith Peak in DM 34. We setup the Global Positioning System's, >lasers and receivers at both ends and established communication on 2 >meter SSB. As soon as it was dark enough I started sweeping the laser >through the area where we thought Smith Peak was. At 02:15 GMT Ward saw >a flash from our laser and with fine tuning we were able to get a solid >sighting by 02:30. We set up the beam modulator and got solid, steady >tone out of the receiver on the Smith peak end. After repeating the >process at the other end, we had steady tone at both ends. Once we had >tone at both ends, we were ready to send CW. Our equipment uses a >rotory solenoid driven by a keyer to interrupt the laser beam to provide >CW communications. The first part of the CW contact was from KC7AED to >WB7VVD at 03:10 GMT contact was concluded at 03:20 Later contacts were >also worked by N7VUB and KC7PCV. >Conditions deteriorated somewhat later in the evening as the air became >hazier but signals remained clear throughout the contact. > >The transmitting equipment at each end consisted of: >A 5 MW Helium Neon laser (red) >12vdc electric fan (the modulator) >12vdc rotory solenoid (beam interrupter) >Keyer /Bencher paddles >The laser and power supply are mounted on a micrometer Azimuth/Elevation >adjustable aluminum stage that allows .001 inch adjustments of the laser >beam. This assembly is attached to a fluid tripod head mounted on a 5 >gallon bucket filled with concrete for stability. The fan and solenoid >assembly sits on a tripod in front of the laser. > >The receiving equipment at each end consisted of: >A 16 inch Fresnel lens >A photo multiplier tube and power supply >An audio amplifier, filter and speaker. >Everything is mounted in a cardboard tube large enough to enclose the >lens and long enough to accommodate the focal distance of the lens. The >cardboard tube we used is from a construction supply house and is >normally used to cast concrete. The tube is painted flat black inside >to reduce reflections and is also mounted on a 5 gallon bucket filled >with concrete. > >We are awaiting confirmation that this distance constitutes a new HeNe >laser record. The strength of the signal and the relative ease with >which we made the contact, convinces us that much longer contacts are >possible with our present equipment. > > 73, Robert N7STU/YB2ARO, DM07aa/OI52ee n7stu@psnw.com http://www.psnw.com/~n7stu (Norcal WSWSS activities & N7STU/YB2ARO homepages) http://www.qsl.net/n7stu (1997 WSWSS Technical Conference Information Page) >From owner-laser Tue Sep 23 03:28:21 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA08862; Tue, 23 Sep 97 03:28:21 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Mon, 22 Sep 97 11:02:23 PDT From: jmoss@berlioz.nsc.com (Jim Moss) Message-Id: <9709221802.AA08104@berlioz.nsc.com> To: laser@qth.net Subject: [LASER] 30mW LDiodes Reply-To: jmoss@berlioz.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk I got requests from: aa1a kd6bq aj6t cmlong mhancock gary.watts markhughes1 fifield Postoffice advises $5 typical depending on where it goes (Parcel Post). Box costs $2.50 per drive... So it will run $17.50 if I mail them. Jim >From owner-laser Tue Sep 23 03:54:26 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA09546; Tue, 23 Sep 97 03:54:26 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Tue, 23 Sep 97 06:19:08 EDT From: sam@stdavids.picker.com (Sam Goldwasser) Message-Id: <9709231019.AA05186@stdavids.picker.com> To: kenbell@cwnet.com, laser@qth.net Subject: Re: [LASER] Schematics for modulating laser diodes/he-ne tubes Reply-To: sam@stdavids.picker.com (Sam Goldwasser) Sender: owner-laser@berlioz.nsc.com Precedence: bulk I need some schematics for modulating laser diodes and he-ne tubes. The couple that I got off the internet are kind of hard to decipher because of the way the lines match up (the resolution is low). Anyway I've looked at a few of the sites and most of it looks like ads, etc. I have a box full (8?) or so laser diodes that I pulled from laser printers mainly. These have the little circuit board on them. I'd like to modulate these either voice or c.w. or what ever I can build a rcvr. to demodulate. Also I need schematics Lots of info and pointers at the sites below. >for rcvrs. I also have some he-ne tubes that work. I made my own power > supply and they seem to work fine, although my 7.5 mw melles griot bellied > up. I bought it at a swap and I powered it up and it seem to work fine so I > put it away because it came in a nice aluminum housing and when Itried to > show a friend my nice find it would'nt work. I pulled it out of the housing > (took awhile) and applied power to it. Well it lit up but no > output...... the tube glows just like the other ones but nothing out of the > end.....any help here?.......Another thing I noticed is that some like to See the FAQ. Might you have whacked one of the mirrors out of alignment? Or, perhaps your current is much too high (2-3X and there will be no output)? If the glow is the same color, it is likely a current or mechanical problem. Only way to be sure is check the spectral lines. I would first check current, then see the section in the FAQ on "How can I tell if my tube is good". > run with reverse polarity? Any help here? I'm using oil filled caps that > are'nt polarized, could they be swapping polarity? My Simpson 260 that goes > to 5 kv brke so i'm stuck with a 1kv. Simpson. Anyway I appreciate all the The may start easier but their life will be shortened - your power supply probably is marginal in the starting department - FIX IT! Too much heating and sputtering at the anode end will degrade the tubes quickly. NOTE: The large can electrode is the cathode! The beam doesn't always come out of the same end - depends on model. If a leaser head, the shell is the negative, ballast is positive. --- sam: Lasers: http://www.geocities.com/CapeCanaveral/Lab/3931/lasersam.htm (Now http://www.misty.com/~don/lasersam.html V3.xx) http://www.pacwest.net/byron13/laserfaq.htm http://www.repairfaq.org/REPAIR/F_laserfaq.html (Formatted!) > help ahead of time..... Would like to get something going for the contests > so I could make some laser contacts or maybe cloud bounce (sounds > cool)......73...Ken > Ken Bell > kenbell@cwnet.com > KC6BWO > > >From owner-laser Tue Sep 23 06:37:57 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA14045; Tue, 23 Sep 97 06:37:57 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Tue, 23 Sep 1997 06:30:45 -0700 From: c1040@azfms.com (Rusty Carruth) Message-Id: <199709231330.GAA21990@fmswksn06.azfms.dot> To: laser@qth.net Subject: Re: [LASER] Roster by location X-Sun-Charset: US-ASCII Reply-To: c1040@azfms.com (Rusty Carruth) Sender: owner-laser@berlioz.nsc.com Precedence: bulk > You can post them here, or to my personnal e-mail at kc5an@prodigy.net > > If there is good response, I will post the results in about a week. > If not, I will abandon the project. > > Meanwile, let me start it: > KC5AN JOHN Near Dallas TX EM12 > N7IKQ Rusty Phoenix,AZ Metro DM43 Only I'm not extremely active right now... rusty >From owner-laser Tue Sep 23 08:37:28 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA17809; Tue, 23 Sep 97 08:37:28 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Tue, 23 Sep 97 08:27:39 PDT From: jmoss@rockie.nsc.com (Jim Moss) Message-Id: <9709231527.AA28428@rockie.nsc.com> To: laser@qth.net Subject: [LASER] laser@qth.net: Non-member submission from ["C. W. Wright" ] Reply-To: jmoss@rockie.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk > Is anyone on the group using APD's? I've just completed an evaluation of Al (k3tkj) and I (k3ap) bought some a few months ago and evaluated them. They have a completly different set of problems than pmts. Unlike pmts, the apd is not good for CW signals, and is quite temperature sensitive where the gain varies with temp. The detector area is very small too. They do work well for IR pulsed lasers though. The ones we uses were Hammamatsu and had bandwidths 1~ ~1.5ghz. Our laser is 1.06 micron with a 1.25ns pulse width and 200 uj powerUnlike pmts, the apd is not good for CW signals, and is quite temperature sensitive where the gain varies with temp. The detector area is very small too. They do work well for IR pulsed lasers though. The ones we uses were Hammamatsu and had bandwidths 1~ ~1.5ghz. The laser has a pulse width of 1.25ns, 200 uj per pulse ( or peak power of 160kw/pulse) and produces 5000 pulses/second. Whe have a doubler on it which produces approx 125 uj of 532nm green as well. We use PMTs to detect the 532nm and they work very well and have excellent bandwidth. If we could get the APDs to work even close to the PMTs, we'd be very happy. -Wayne ----- End Included Message ----- >From owner-laser Tue Sep 23 10:25:17 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA20791; Tue, 23 Sep 97 10:25:17 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <199709231711.MAA01046@ultra.qni.com> From: "Gary Watts" To: "KC5AN" , "Laser Reflector" Subject: Re: [LASER] Roster by location Date: Tue, 23 Sep 1997 12:10:50 -0700 X-Msmail-Priority: Normal X-Priority: 3 X-Mailer: Microsoft Internet Mail 4.70.1160 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Reply-To: "Gary Watts" Sender: owner-laser@berlioz.nsc.com Precedence: bulk Willing to try just about anything :-) Gary Watts N0OXV Kansas CIty Mo. EM29RE 816-454-3569 Dale Lam WA0NKE Kansas City Mo EM29RE 145.43 - ---------- > From: KC5AN > To: Laser Reflector > Subject: [LASER] Roster by location > Date: Monday, September 22, 1997 6:10 PM > > For those of us who might want to sked & meet for QSO, I would like to > establish a roster, by location. I will (and believe me--- I rarely > volunteer for ANYTHING) keep and maintain a list of active laser > operators, sorted by state (or country, for our non-U.S. fellow > fanatics), if there is enough response to show that others car about > having the same information. > > All needed is your on-air name, your callsign (if you are a ham), > your city & state, and your gridsquare. > > You can post them here, or to my personnal e-mail at kc5an@prodigy.net > > If there is good response, I will post the results in about a week. > If not, I will abandon the project. > > Meanwile, let me start it: > KC5AN JOHN Near Dallas TX EM12 >From owner-laser Tue Sep 23 15:32:06 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA02812; Tue, 23 Sep 97 15:32:06 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f From: daveaa1a@xensei.com Date: Tue, 23 Sep 1997 18:25:17 -0400 Message-Id: <199709232225.SAA20296@xensei2.xensei.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Subject: [LASER] Laser transmit focus To: laser@qth.net X-Mailer: SPRY Mail Version: 04.00.06.17 Reply-To: daveaa1a@xensei.com Sender: owner-laser@berlioz.nsc.com Precedence: bulk Gudday.. The other day I found a 35mm telephoto lense at a yard sale with a 1/4"-20 threaded base ring.. The bayonet mounting ring easily holds a piece of 1-1/4" aluminum tubing secured within it's inside threads.. The tubing is about 5" long.. A surplus laser diode/colimated fixture is slid up inside the tubing so as to spread a beam almost the width of the first lense.. (when it is at focus).. I set the focus of the lense to 40' (the distance to my tower) and push the diode/fixture in and out until a BRIGHT PIN-POINT beam appeares on the old number plate.. Then I rotate the focus to INFINITY and the spot beam at the number plate reflector becomes a very clear, bright circle the size of the object lense.. (300mm).. This to me is the easiest way to focus a laser diode/collimator into a TUBE of light and gives you much smoother control over the divergence of the beam.. In the case of IR diodes, a ccd camera will let you see what is taking place at the beam when your eyes run out of bandwidth.. eg:780 nm.. For the scatter transceiver I mount the CCD camera, the 35mm lense transmitter and the 4" pvc receiver all on a camera bar with a hand-hold grip or use the bar threads for mounting onto the tripod.. The next generation transmitter will be an old 35mm camera with the diode and modulator mounted within the camera... Now for a clear night...(!!)... 73s from Dave www.qsl.net/aa1a >From owner-laser Wed Sep 24 01:44:41 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA20578; Wed, 24 Sep 97 01:44:41 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f From: "BARRY CHAMBERS" To: laser@qth.net Date: Wed, 24 Sep 1997 09:38:42 +0100 Subject: [LASER] opt210 layout X-Mailer: Pegasus Mail for Windows (v2.42a) Message-Id: <161300BDF@ramsden.shef.ac.uk> Reply-To: "BARRY CHAMBERS" Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi As a newcomer to the group, can I ask for advice on any precautions to be taken when laying out the components around an OPT210 ? Is it OK to use an IC socket or is it better to bend the IC leads out and mount the IC close to a ground plane and air-wire the rest of the components around it? I have in the past played with 2mw HeNe lasers which are readily available in the UK but now cheap laser pointers (stlg15 = $25) are available at hamfests. Some are in the usual pen style casing but one made by Altai is in a rectangular plastic case and comes complete with a built-in extendable pointer. This one is easy to modify as the case can be discarded, leaving the laser module/psu in a neat metal tube, complete with glass lens assembly. 73 Barry G8AGN, co-editor of RSGB Microwave Newsletter +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Dr Barry Chambers Reader in Microwave Engineering Dept of Electronic & Electrical Eng University of Sheffield Mappin St email: b.chambers@sheffield.ac.uk Sheffield phone: +44 (0)114 222 5588 S1 3JD, U.K. fax: +44 (0)114 272 2097 WWW URL:http://www.shef.ac.uk/~el1bc >From owner-laser Wed Sep 24 03:59:24 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA22163; Wed, 24 Sep 97 03:59:24 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Message-Id: <2.2.16.19970924104528.8ccfb746@personal.eunet.fi> X-Sender: oh2aue@personal.eunet.fi X-Mailer: Windows Eudora Pro Version 2.2 (16) Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Wed, 24 Sep 1997 13:45:28 +0300 To: "BARRY CHAMBERS" , laser@qth.net From: Michael Fletcher Subject: Re: [LASER] opt210 layout Reply-To: Michael Fletcher Sender: owner-laser@berlioz.nsc.com Precedence: bulk Barry, What I did whas to build the whole "front end" into a small tin plated enclosure. The box is fed by 12 V dc and supplies Zener regulated + - 10 V to the OPT210. The negative supply I have generated via a surplus simple switch mode supply intended for generating HV for discharge displays. The PSU is a very simple dual transistor switcher with a toroidal transformer. This could be replaced with a 555 or 4093 oscillator and diode multipliers in the reverse direction. Or simply feed the thing single-ended. My RX also includes a 72 MHz oscillator feeding an RMS-1 mixer directly without doubler. The IF is attenuated by over 30 dB with a pad, protecting the mixer from accidental reverse RF ( in addition to decreasing the phenomenal gain of the OPT210 - I am using 1 Mohm feedback in this unit ). The OPT210 I have soldered directly onto the edge of a piece of breadboard PCB soldered upsidedown onto a PCB groundplane. In this way I have a little flexibility to adjust the focal point. I soldered a chimney onto the side of the tin box to support a lense. This chimney diameter fits my telescope ocular. I have no leakage from the swiching PSU and no hum of any kind. I have also implemented an audio output from the OPT210 to use with mechanically modulated HeNe laser carriers. Michael _\\///_ _ _ _ (' O O ') (_()_()_) I.O.O.F. *------------ooO-(_)-Ooo---------------------------* * Michael Fletcher OH2AUE: 50 MHz * * Vanhaistentie 4 C 43 144 MHz * * FIN-00420 Helsinki 432 MHz * * 1296 MHz * * Phone/Fax + 358 9 566 62 63 home 2.304 GHz * * Cellular + 358 50 5505 293 3.400 GHz * * Phone + 358 9 5259 1890 work 5.760 GHz * * http://personal.eunet.fi/pp/oh2aue/ 10.368 GHz * * 24.092 GHz * * Life is above 1 GHz; 474 THz * * >99.9 % of the ham bands are there..... * *--------------------------------------------------* >From owner-laser Wed Sep 24 09:21:35 1997 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA28205; Wed, 24 Sep 97 09:21:35 PDT X-Authentication-Warning: ns3.qth.net: majordom set sender to owner-laser@qth.net using -f Date: Wed, 24 Sep 97 09:12:23 PDT From: jmoss@rockie.nsc.com (Jim Moss) Message-Id: <9709241612.AA28384@rockie.nsc.com> To: laser@qth.net Subject: [LASER] BB layout Reply-To: jmoss@rockie.nsc.com (Jim Moss) Sender: owner-laser@berlioz.nsc.com Precedence: bulk I used perf board and ran the detected signal out to a 1/8" connector. Wrapped the whole thing in aluminum foil (except the opening for the detector). Foil was grounded to battery. Used a resistor divider for the single supply operation. I used a few 27MOhm resistors for the feedback. Then mounted the foil package to the back side of a lens cap (with a hole in the middle). This way the detector can be placed on a pair of binoculars or telescope. A seperate audio amp is fed by the BB. It's cheap, it's not pretty, but it works, and has no RFI. Jim N9JIM (ex-WB9AJZ) CM87xi Sunnyvale, CA