From majordomo-owner@berlioz.nsc.com Mon Mar 3 15:53:57 1997 Date: Mon, 3 Mar 97 15:53:56 PST To: jmoss From: majordomo@berlioz.nsc.com Subject: Majordomo file: list 'laser' file 'laser.9603' Reply-To: majordomo@berlioz.nsc.com Content-Length: 46101 -- >From owner-laser Fri Mar 15 15:32:18 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA23460; Fri, 15 Mar 96 15:32:18 PST Date: Fri, 15 Mar 96 15:32:16 PST From: jmoss (Jim Moss) Message-Id: <9603152332.AA23453@berlioz.nsc.com> To: laser Subject: test Sender: owner-laser@berlioz.nsc.com Precedence: bulk did you get this??? >From owner-laser Mon Mar 18 21:36:59 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA09155; Mon, 18 Mar 96 21:36:59 PST Date: Mon, 18 Mar 1996 21:34:11 -0800 Message-Id: <199603190534.VAA01340@ix14.ix.netcom.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit From: sjnoll@ix.netcom.com Subject: Duz this werk? To: laser@berlioz.nsc.com X-Mailer: SPRY Mail Version: 04.10.06.22 Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hello.. hello? Test of this mail server sent 9:35 PST 3/18/96 Steve J. Noll | Ventura CA | WA6EJO | IEEE | AVS | sjnoll@ix.netcom.com >From owner-laser Tue Mar 19 05:57:20 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA18351; Tue, 19 Mar 96 05:57:20 PST Message-Id: <199603191355.AA260033743@host-04.colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Tue, 19 Mar 1996 13:55:31 +0000 To: laser@berlioz.nsc.com From: "Art Allen, KY1K" Subject: test Sender: owner-laser@berlioz.nsc.com Precedence: bulk test >From owner-laser Tue Mar 19 08:59:19 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA21644; Tue, 19 Mar 96 08:59:19 PST Date: Tue, 19 Mar 96 08:59:15 PST From: jmoss (Jim Moss) Message-Id: <9603191659.AA21638@berlioz.nsc.com> To: laser Subject: Sign ons.... Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hopefully you all got WELCOME to LASER Messages from the system. I had to manually approve for Kent.e.britain@tek.com lmcpegr@lmc.ericsson.se Kent actually has "bangate" after the @ and before the "tek". LMC actually has "langate" after the @ and before the "lmc". The server is picky. So no need to fix it now. But to unsubscribe they will need my help. You can see who is signed up at any point by sending a message to majordomo, with a command "WHO LASER" in the body. It will return a list of all the subscribers. The only ones we are still missing is Walt AJ6T and NC1K. Jim WB9AJZ/6 >From owner-laser Tue Mar 19 09:01:44 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA21731; Tue, 19 Mar 96 09:01:44 PST Date: Tue, 19 Mar 96 09:01:42 PST From: jmoss (Jim Moss) Message-Id: <9603191701.AA21725@berlioz.nsc.com> To: laser Subject: Majordomo results Sender: owner-laser@berlioz.nsc.com Precedence: bulk Here is the list as of 3/19/96 9:00 AM PST Jim ----- Begin Included Message ----- >From majordomo-owner@berlioz.nsc.com Tue Mar 19 09:00:30 1996 Date: Tue, 19 Mar 96 09:00:29 PST To: jmoss From: majordomo@berlioz.nsc.com Subject: Majordomo results Reply-To: majordomo@berlioz.nsc.com Content-Length: 174 -- >>>> who laser Members of list 'laser': kevinhague@aol.com jmoss sjnoll@ix.netcom.com daveaa1a@pcix.com aballen@colby.edu kent.e.britain@tek.com lmcpegr@lmc.ericsson.se ----- End Included Message ----- >From owner-laser Wed Mar 20 09:02:28 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA01953; Wed, 20 Mar 96 09:02:28 PST Date: Wed, 20 Mar 96 09:02:26 PST From: jmoss (Jim Moss) Message-Id: <9603201702.AA01945@berlioz.nsc.com> To: laser Subject: Majordomo results Sender: owner-laser@berlioz.nsc.com Precedence: bulk All, I think everyone is on! Jim (reminds me of a classic comment... "If anyone doesn't get this let me know!") ----- Begin Included Message ----- >From majordomo-owner@berlioz.nsc.com Wed Mar 20 09:01:11 1996 Date: Wed, 20 Mar 96 09:01:09 PST To: jmoss From: majordomo@berlioz.nsc.com Subject: Majordomo results Reply-To: majordomo@berlioz.nsc.com Content-Length: 202 -- >>>> who laser Members of list 'laser': kevinhague@aol.com jmoss sjnoll@ix.netcom.com daveaa1a@pcix.com aballen@colby.edu kent.e.britain@tek.com lmcpegr@lmc.ericsson.se aj6t@slip.net nc1k@pcix.com ----- End Included Message ----- >From owner-laser Wed Mar 20 21:49:28 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA25713; Wed, 20 Mar 96 21:49:28 PST Message-Id: <3150EB1C.6ABF@pcix.com> Date: Thu, 21 Mar 1996 00:37:32 -0500 From: Merv Organization: pcix X-Mailer: Mozilla 2.0GoldB1 (Win95; I) Mime-Version: 1.0 To: laser@berlioz.nsc.com Subject: I,m here... Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-laser@berlioz.nsc.com Precedence: bulk Merv, NC1K, checking in. >From owner-laser Wed Mar 20 22:21:12 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA26369; Wed, 20 Mar 96 22:21:12 PST Date: Wed, 20 Mar 1996 22:16:35 -0800 Message-Id: <199603210616.WAA04278@ix5.ix.netcom.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit From: sjnoll@ix.netcom.com Subject: Schematic & Photo Exchange To: laser@berlioz.nsc.com X-Mailer: SPRY Mail Version: 04.10.06.22 Sender: owner-laser@berlioz.nsc.com Precedence: bulk I've been wondering if the popular video capture device called the "Snappy" would be capable of rendering schematics. If so, it will convert them to JPGs that we could easily exchange. Images of our laser platforms, receiver circuit boards, etc., could be shared in the same way - and much easier that photographing them and then scanning them. I've never seen one at work so I don't know if a Snappy & video camera would be capable of seeing the fine lines of a schematic well. I believe it costs under $200, which is far cheaper than a full-page scanner, let alone a color one. Anyone had any experience with one of these? 73, Steve J. Noll | Ventura CA | WA6EJO | IEEE | AVS | sjnoll@ix.netcom.com >From owner-laser Thu Mar 21 10:02:26 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA11689; Thu, 21 Mar 96 10:02:26 PST Message-Id: <199603211800.AA048941248@host-04.colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Thu, 21 Mar 1996 18:00:28 +0000 To: laser@berlioz.nsc.com From: "Art Allen, KY1K" Subject: Kodak filter specs needed Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hey everyone, Been dubbin around the basement, cleaning up the 'parts bin'. You all know what it's like...u know u got it somewhere, but damned if u can find it hi hi. Well, during this mornings search and rescue mission, I found a Kodak filter, about 1.5 by 1.5 inches, in a padded envelope. It's definately red, and I dont really know how to tell if its narrow band or not. Barb remembers purchasing a narrow band green filter years ago, but not a red one... Anyway, it's a numer 29, Kodak Wrattten Gelatin Filter. Anyone got specs, esp'ly bandwidth?? How can u estimate the bandwidth by eyeballing it?? It might be a low pass or a high pass filter also? Any ideas? You know how to reach me...Art... >From owner-laser Thu Mar 21 10:03:30 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA11721; Thu, 21 Mar 96 10:03:30 PST Message-Id: <199603211801.AA049811312@host-04.colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Thu, 21 Mar 1996 18:01:33 +0000 To: laser@berlioz.nsc.com From: "Art Allen, KY1K" Subject: Re: Schematic & Photo Exchange Sender: owner-laser@berlioz.nsc.com Precedence: bulk At 10:16 PM 3/20/96 -0800, you wrote: >I've been wondering if the popular video capture device called the >"Snappy" would be capable of rendering schematics. If so, it will >convert them to JPGs that we could easily exchange. Images of our laser >platforms, receiver circuit boards, etc., could be shared in the same >way - and much easier that photographing them and then scanning them. >I've never seen one at work so I don't know if a Snappy & video camera >would be capable of seeing the fine lines of a schematic well. I >believe it costs under $200, which is far cheaper than a full-page >scanner, let alone a color one. Anyone had any experience with one of >these? > >73, > >Steve J. Noll | Ventura CA | WA6EJO | IEEE | AVS | sjnoll@ix.netcom.com > > Hey everyone... Yes, we need to be able to send schematics. Obviously, the best way, in terms of data file size is with a software package that is made for drawing schematics...the files are very small and compact. I've kinda written them off tho, becuase not all of us have pc's and because we might want to send an 'already existing schematic' and its alot of work to redraw them using the software... But, scanners on the other hand create bitmaps or gifs or jpeg. I think 'color' goes beyond our needs and make a black and white 'schematic' alot larger than it has to be. Anyone with a vga monitor can handle a bitmap or gif or jpeg.. So, I dont think the 'type' of file is to important, as long as its universal. Scanners are becomming cheeper and they are all over the place now. I think the answer might be to 'hurry up, and wait' on this one... If someone really needs something scanned for the group, I can do it and ship the results back via inet. We have a scanner we can 'borrow' hi hi. Bye for now and GL..Art... >From owner-laser Thu Mar 21 19:12:28 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA01118; Thu, 21 Mar 96 19:12:28 PST Message-Id: <199603220310.AA014624220@host-04.colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Fri, 22 Mar 1996 03:10:11 +0000 To: laser@berlioz.nsc.com From: "Art Allen, KY1K" Subject: red dots ??? Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hey Everyone... Been dubbin around with bore sights...they have the needed resolution, but, in the dark, u cant identify the far end of the tube and the close end of the tube, so that when u do get the beam within the bore sight, u cant tell whether its high, low or to the left or what... So, atleast at night, I can see the drawbacks! It looks like they would be FB, if we were doing daylight IR shots tho! Anyway, Im thinking about illuminating the bore sight, on both ends, but thats easier said than done, since the illumination source interferes with the sightling of the target!!! So, there we are...back to the beginning again! Hey, years ago, when the pistols first starting having scopes, I saw what they called a 'red dot' scope. It appeared to be a large (maybe 1 nch diameter) window, with a red dot in the middle of it. The intensity of the red dot was adjustable, and looking thru the scope, the red dot appeared to 'float' there. Im thinking of using the same 'floating red dots' for aiming...one red dot on the far end of the laser tube, one at the close end..and when the 2 dots on the laser and the target are all in line...PRESTO. Target lock! I'd love to try one of those red dot scopes for this, pistol scopes are much lower power and have a much wider admittance angle and way BIG eyepieces, so it might be just what we need! Last time I saw one advertised, they were about 189 bucks...way outta my budget. Obviouly, even the smallest fiber optic cable would interfere with the optics and I tried punching some small holes in glass and side illuminating it with an LED...no luck.. Anyone have any idea how they make that floating red dot, without messing up the optical path?? Theres gotta be an easy way to do it!!! Any floating red dot experts out there ?? Art.... >From owner-laser Tue Mar 26 12:13:03 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA20901; Tue, 26 Mar 96 12:13:03 PST Date: Tue, 26 Mar 1996 12:07:24 -0800 (PST) From: Walter Miller To: "Art Allen, KY1K" Cc: laser@berlioz.nsc.com Subject: Re: Kodak filter specs needed In-Reply-To: <199603211800.AA048941248@host-04.colby.edu> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-laser@berlioz.nsc.com Precedence: bulk On Thu, 21 Mar 1996, Art Allen, KY1K wrote: > > Anyway, it's a numer 29, Kodak Wrattten Gelatin Filter. > > Anyone got specs, esp'ly bandwidth?? How can u estimate the bandwidth by > eyeballing it?? It might be a low pass or a high pass filter also? > > Any ideas? You know how to reach me...Art... > > Hello Art and the laser gang, I talked to a friend of mine who has the specs on Kodak Wratten filters, and he said the number 29 is a filter with a cutoff wavelength of about 610 nm. It transmits wavelengths LONGER than 610 nm. Here are a few words of introduction about myself. I have been interested in laser communication for a long time, but have not actually put anything on the air yet. I have a few solid state red lasers kicking around in my junkbox from last year's flea markets, and I plan to dedicate a Celestron C90 telescope to the project. I also have some old HeNe tubes going gassy in the junkbox, but the diode lasers are more attractive for experimentation. I am currently an engineering manager for a small government contractor at NASA Ames Research Center, and in an earlier lifetime in the 1970s I worked for Spectra Physics as a manufacturing engineer and project engineer....most of my experience there was with tuneable dye lasers. My current ham radio projects include digging out the last few QSL cards needed for VUCC on 2 meters, finding another 10 countries on topband for 160M DXCC, and scheming about a laser setup for the June contest. How about some other short bios from the other members of this laser reflector? 73, Walt ------------------------------------------------------------------------ Walter Miller, AJ6T Saratoga, CA USA CM87 Reply to aj6t@slip.net >From owner-laser Wed Mar 27 10:05:27 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA26261; Wed, 27 Mar 96 10:05:27 PST Date: Wed, 27 Mar 96 10:05:21 PST From: jmoss (Jim Moss) Message-Id: <9603271805.AA26248@berlioz.nsc.com> To: laser Subject: corner reflectors Sender: owner-laser@berlioz.nsc.com Precedence: bulk Has anyone done much experimenting with a corner reflectors? Seems like a good target with a "wide" tolerance for input angles. I see commercial 5" ones listed in Edmund Sci catalog but expensive. I am considering "building" one. Looks like the tolerances are fairly tight, but achievable. I was considering using 5 or 6" polished semiconductor wafers as reflectors. Not sure how good they are for reflectors, perhaps aluminized would help. But.. they are very uniformly flat. The critical issue is creating the "perfect" 90 degree references/mechanics for mounting. Any thoughts... is this all fooey? Jim WB9AJZ/6 Sunnyvale. >From owner-laser Wed Mar 27 16:07:36 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA05773; Wed, 27 Mar 96 16:07:36 PST Message-Id: <199603280005.AA197841550@host-04.colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Thu, 28 Mar 1996 00:05:40 +0000 To: laser@berlioz.nsc.com From: "Art Allen, KY1K" Subject: Re: corner reflectors Sender: owner-laser@berlioz.nsc.com Precedence: bulk At 10:05 AM 3/27/96 PST, you wrote: >Has anyone done much experimenting with a corner reflectors? Seems like a good >target with a "wide" tolerance for input angles. I see commercial 5" ones listed >in Edmund Sci catalog but expensive. > >I am considering "building" one. Looks like the tolerances are fairly tight, >but achievable. I was considering using 5 or 6" polished semiconductor wafers as >reflectors. Not sure how good they are for reflectors, perhaps aluminized would >help. But.. they are very uniformly flat. The critical issue is creating the >"perfect" 90 degree references/mechanics for mounting. > >Any thoughts... is this all fooey? > >Jim WB9AJZ/6 Sunnyvale. > > Hey Jim, I worked for Fairchild Semiconductor for 4 years in the equipment engineering department. The job gave me alot of chances to rub elbows with the Process Engineers, and stuff like that. I actually discussed this subject with one of them once. The silicon wafer is damn close to a perfect mirror, esp'ly these days, as the geometry gets smaller and smaller on the wafers. This applies to tollerences of the surface only. As a mirror, its quite good too, it has to be actually...its a slice of a perfect crystal of silicon, so its pretty shiney. Probably, and aluminum surface would make it worse, the oxidation on aluminum is multiple molecules thick, for oxidation on silicon, its only believed to be a single molecule.. My guess is that the MOUNTING of the wafer will be the real problem. Since they are thin, they flex (ever so slightly). Mounting of extremely precise telescope optical surfaces involves the same problems, and glass used for them is many times the thickness of that wafer! All depends what kind of tollerence you are looking for. Im not quite sure what you would actually use a corner reflector for, I presume you would align it so that it would return a laser beam to the sender (as the reflector on the moon and various earth orbiting satellites do). Incidently, when I worked at Fairchild, they had a real strict policy about wafers leaving the factory...and, for good reason. I was never able to get one out. If u have a source for them, I'd sure like to have some bare wafers, or even decent sized pieces. I've just learned OH2AUE is qrv on laser too, and have asked him if he was interested in joing the group. Bye and GL..>Art... >From owner-laser Wed Mar 27 16:56:34 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA07560; Wed, 27 Mar 96 16:56:34 PST Date: Wed, 27 Mar 96 16:56:31 PST From: jmoss (Jim Moss) Message-Id: <9603280056.AA07535@berlioz.nsc.com> To: laser Subject: corner reflectors Sender: owner-laser@berlioz.nsc.com Precedence: bulk The idea I had was to use a corner reflector as a remote target, to assist in getting the aiming problem improved. I started reading some extracts of papers presented at a couple conferences over the last year, and there were a few that mentioned the use of corner reflectors on satellites. There were even more about plane to plane and plane to ground. Sounds like there is high intrest in secure links and high speed links. I've applied thru our local tech library to get a copy of the precedings. BTW... I'm still thinking LOW POWER (<5mW) and low cost (<$100) to put most stuff together. (we already have made a mile with some very simple equipment) Mounting wafers is of course a problem, but not unsolvable. I've got some machinist friends, and I'm talking to them about what it would take to make a "perfect" corner. Other options (and probably much cheaper) would be to build it with some adjustments and align it using the laser itself. The neat thing about the corner is whatever angle goes in, is what comes out, so a large area could be covered with it. If we mounted one up on the mountains above San Jose, anyone who would be within a large chunk of the valley would be able to target it, with round trip capability. Another use, would be for alignment in contests. If each station had one, and had their RX close enough (depends on beam size), they could each align themselves, without the need for VHF/UHF feedback. Jim WB9AJZ/6 Sunnyvale. >From owner-laser Wed Mar 27 17:06:57 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA07891; Wed, 27 Mar 96 17:06:57 PST Date: Wed, 27 Mar 96 17:06:54 PST From: jmoss (Jim Moss) Message-Id: <9603280106.AA07885@berlioz.nsc.com> To: laser Subject: WB9AJZ 670nM station profile Sender: owner-laser@berlioz.nsc.com Precedence: bulk Think Walt had a good idea here's my profile. 3/27/96 Jim Moss WB9AJZ/6 Sunnyvale CA CM87xi Longest DX = 0.8 Miles TX: 5mW 670nM laser. Mounted with az-el fixture (allowing 1mR resolution) on a camera tripod. Modulated full on/off, at 800 Hz bursts controlled by a memory keyer. RX: Simple phototransistor (RS) thru 2 stages of op-amp to headphone. 7" parabolic mirror w/24" focus. (second surface mirror) Co-mounted on camera tripod. DSP 9+ available for audio filtering. Currently researching aiming techniques. No experiments running at this time. I have 2 working RX's now. No equipment for measuring power or sensitivity, other than relative measurements. Also looking into possibility of using SIR, MIR, FIR standards (Infra Red for computers) as a way to send digital signals over the laser. If the TX/RX can handle the speeds (100Kbps, 1Mbps, 4Mbps) Some of the aiming issues may be minimized by sweeping(?) across the target. >From owner-laser Thu Mar 28 06:13:33 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA25528; Thu, 28 Mar 96 06:13:33 PST Message-Id: <199603281411.AA019142302@host-04.colby.edu> X-Sender: aballen@colby.edu (Unverified) X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Thu, 28 Mar 1996 14:11:34 +0000 To: oh2aue@personal.eunet.fi (Michael Fletcher) From: "Art Allen, KY1K" Subject: Re: qrv on 474 thz? Cc: laser@berlioz.nsc.com Sender: owner-laser@berlioz.nsc.com Precedence: bulk At 09:54 AM 3/28/96 +0200, you wrote: >>Hi Michael > >Hi Art > >Well, sounds interesting, the reflector. Hopefully you aren't overloaded >with traffic ? I am already assigned to a few lists concerning EME, weak >signal, DSP, AMSAT, and a couple of very technically orientated ham-tech >lists here in Finland + many more. The amsat lists are very important, as >AMSAT-OH is delivering hardware for P3D ( the 10 GHz transmitter ). > >I havn't been too active on 474 for a couple of years, but the idea stirs >the mind occasionally. What I have been using is a couple of HeNe Lasers >of about 20 - 30 mW for CW. Simple fan modulators and modified relays for >keying optomechanically so to speak. Receivers are simple red LED's with >a little bias and optics. Been looking around for overhead projector >Fresnel lenses ( seen then for low price in Edmund Scientific catalogues ). >Have 110 mm refractor telescope for DX... >Purchased a couple of cheap laser pointers, and found they can be square >wave modulated up to several MHz, so a new field opens for PWM, FM and the >like. Photomultipliers would be nice, but I simply haven't had the time ! > >I have access to several line of site QTH's for ranges of 1 - 70 km. >Used a laser for a simple magnetometer a few years back - looks impressive ! >Also tried mixing to laser signals in an avalanche diode, not much success >though. Objective ? Dunno. Maybe phase locking for coherent comms ? Just >interested I suppose. Played arount with prisms and such. Would LOVE to >lay hands on an electro-optical modulator for AM/FM and a Bragg element >for GHz range acousto-optical real time spectrometer through a CCD element: >I am very interested in amateur radio astronomy in the microwave domain > >Sign me on please ! > > Michael > _\\///_ > (' O O ') > *------------ooO-(_)-Ooo-------------------------* > * Michael Fletcher OH2AUE: * > * Vanhaistentie 4 C 43 50 MHz * > * FIN-00420 Helsinki 144 MHz * > * 432 MHz * > * Phone/Fax + 358 0 566 62 63 home 1.296 GHz * > * Fax + 358 0 146 4855 work 2.304 GHz * > * Phone + 358 0 1480 7521 work 5.760 GHz * > * Cellular + 358 50 5505 293 work 10.368 GHz * > * 24.092 GHz * > * Life is above 1 GHz; 474 THz * > * >99.9 % of the ham bands are there..... * > *------------------------------------------------* > > > Hi Michael, Glad u are interested in further development in of laser comm. Our laser group is very small, 7 users in the reflector at present... Its a pretty specialized topic, so there is not a big flood of users to the reflector! You will not have a big volume of mail from it, so it wont increase your connect time by much. I have forwarded this message to our group, and will bounce the sign up instructions to you later today. Its a standard listserv reflector. I do not know if archived info is available, but the group is new and there wouldnt be much in the archive anyway! So, good luck, and welcome aboard. Please pass the word to anyone else who might be interested. Art.... >From owner-laser Thu Mar 28 08:45:34 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA01426; Thu, 28 Mar 96 08:45:34 PST Message-Id: <199603281645.AA098991517@host-04.colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Thu, 28 Mar 1996 16:45:10 +0000 To: laser@berlioz.nsc.com From: "Art Allen, KY1K" Subject: high accuracy aiming methods #1 Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hey everyone, What follows will be long and boring to some, hopefully, it will be usefull to those just starting out. Some number of weeks ago, I told the group I was dedicating my time here to R + D of aiming methods. I have developed some very promissing 'hands off' aiming methods, atleast on the protype 'indoor' range scale. About half way thru this development, I began to wonder why I was messing with 'getting the aiming close, then randomly sweeping' method. In the process of development, it became increasingly clear that a 'put it on target within 1 or 2 mrad, and don't worry about random sweeping' technology might be possible. So, I've switched gears here, to some degree, and would like to report on my research to date. Mechanical methods of actually MOVING the beam are not discussed here. Instead, I am going to report regarding precision aiming, that is, 'how to confirm that we are actually pointed exactly at the target'. --------------------------------------------------------------------------- Method #1-Bore sights. Many of us have used bore sights for eme arrays, aiming of dishes other applications. A 'precision' bore sight is possible, and I started out with this approach. I found that a .75 cm plastic tube, about 5 inches long provides about 10-12 millirad field of view if the eye was 2 or 3 inches from the tube. Moving back further, in the 2 or 3 foot range, a 3 to 5 mrad field of view was possible. I mounted such a tube to my small HENE laser, using angle brackets and shimming the rear support for AZ and the front support for EL. On the indoor test range, it was rare when I could not aim the laser within 2-3 mrad! Hey, that sounds great, and it was. On the outdoor test range, at night, however the bore sight falls apart however! The problem I observed, that really kills the 'simple' bore sight, is that you cant see the eyepiece and the far end of the boresight in the dark..hence, its really tough to utilize the ultimate 'precision' that it is capable of producing. In the daytime, when u can see both ends of the boresight relative to each other, it is 100 percent capable of providing the needed resolution though. I conclude that for daylight laser shots, a boresight would be an outstanding choice. -More Bore Sights. Before leaving this topic, I should add that various illumination methods were tried. I figured, if I could light up the far end of the tube (maybe in yellow) and the eye end of the tube (maybe in green), then I could simply line up the different colored rings, and then check to see that the red target was in the middle of that circle! A sound concept, but I could not figure out a way to do this easily and cheeply! Thied various schemes using end illuminated tygon tubing, and some fiber optic cable... Just couldnt get it right. This might provide a viable night time sighting method, if this problem could be overcome! Ideas???? Additionally, I found the boresight to be practically bullet proof, as far as being 'rugged'. My first tries involved screws to align the boresight..hard to build and fragile. By 'shimming' with thin sheets of saran wrap and scotch tape, I found that I could remove the bore sight (its held in place against the shims with a rubber band), stress both mounting brackets, play 'fetch the bore sight with the dog', then reinstall the bore sight on the laser. It always points to the same point-very rugged and virtually impossible to knock out of alignment. I would think that the actual mounting of the laser tube in the enclosure would be the limiting factor here.... --------------------------------------------------------------------------- Method #2-2nd generation optical alingment. In my dubbing around, I began to see the light regarding the bore sight method. I reasoned, that, if I could use some small lights, one on each end of a tube, then line up those lights with the target..presto. No need to randomly scan or hunt for the target, if the resolution of the aiming was less than (better than) the divergence of the laser. If it was possible to build a rugged and cheep optical alignment system, then we could just point the laser in the general direction of the target, adjust the position so that the target lines up, then u are home free. If the aiming has good resolution, and is reproducable, then u dont even need to turn the laser on while u adjust its position! Just point and click. SOUNDS GREAT! So, how to do it tho??!! One method, which I found was to use a 3/4 inch piece of pvc pipe and mount window glass at 45 degree angles on each end of the pipe. Then, a small LED, placed in the tube and pointed at the glass would produce a small lighted dot at the eyepiece of the tube. So, the result is a floating lighted dot on the far end of the tube and the same at the eyepice end of the tube. You sight thru the tube, since the glass is optically flat, there is no major distortion in the direction of the target due to the 45 degree tilt. The function of the 45 degree tilt in the glass is to provide a reflecting surface for the small LED's, so that they are reflected BACK towards the eyepiece. So, u have resolution that is only limited by the size of the small floating lighted dots (and your eesight)! I used a sewing needle heated red hot on the stove in order to 'drill' a small round hole for the light source. Works good! My first version was about 3 inches long and was illuminated with fibre optics. It worked FB too. Not quite enuff resolution for the 2 mrad laser, probably very practical for a 3-4 mrad solid state tx-just a guess. At present, Im testing a 7 inch long unit, and it appears VERY VERY promissing. The 7 inch tube Im working on has the illuminating LEDS mounted directly at the pinhole on the tube, so, if the glue holds, it too should be pretty rugged! No moving parts to get knocked out of alignment. I havent mounted this setup on the laser yet. Indoors, in the daytime, the 'floating dots' are highly visable and it is easy to aim. The big advantage here is that u dont rely on the sides of the tube for reference, so it should work well outside (at night) also. At night, the floating dots are too bright, havent dimmed them down yet, but even with boarderline blinding bright illumination, it looks very very promissing! My hope it that, ultimately, I can align the front and rear 'dots', then compare that single dot to the location of the target. When all three dots are lined up in the eyepiece, then PRESTO-target lock (I hope). Hopefully, with green illumination in the scope, when target lock is achieved, the color should turn to brown (I think)...assuming a red target hi hi. Sounds neat, dont know if it works yet, but Ive tested sighting in on a red LED at 300 feet away, at night and the led is resolvable, along with the green illumination in the tube. --------------------------------------------------------------------------- In the future- Hey guys, when I was a little tyke, I could literally place 5 shots from my 22 target rifle within a half inch circle at 50 feet, using crude 'peep' sights. It was not uncommon to punch the center of the target out and when I got really good, I would shoot 2 rounds at each target, because sometimes the rounds would go through the same holes at 50 feet. Well, my 2 mrad laser makes about a 3/4 inch dot on the wall at 20 feet (+/-). I can aim much better than that, esp'ly with an appropriate sighting mechanism. It has occurred to me, that maybe a tripod and aiming mechanism isnt needed at all, just mount the laser and lighted scope on a rifle like 'stock', lay down on the ground and aim that thing at the target-if there was electronic data transmission, your entire 2 way qso could take place in half a second flat!!! Even if u couldnt quite hold the laser on the target all the time, similar setups on each end would probably make laser Q's fast, easy and simple. VUCC in 2 minutes flat anyone ???? Just a thought.... --------------------------------------------------------------------------- Hey guys, am I missing something here?? I havent tested the idea as much as I would like to, but I feel pretty comfortable reporting it to the group for their comments and consideration. Am I all wet here or missing something really important??? OK, this ends our normally scheduled program, returning to sanity...... Art.... >From owner-laser Thu Mar 28 09:00:22 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA01827; Thu, 28 Mar 96 09:00:22 PST From: kent.e.britain@bangate1.tek.com Date: Thu, 28 Mar 96 6:55:08 CST Message-Id: X-Priority: 3 (Normal) To: Subject: fwd: First Try Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-laser@berlioz.nsc.com Precedence: bulk ------------- Original Text >From Kent E Britain, on 3/26/96 2:45 PM: To: tekmail[majordomo@beriloz.nsc.com] OK, let's see if I can this a message to the reflector. Steve, I've got a 2 hour video tape made by KY7B and company of the 154 mile QSO. The laser was easy to see in the camera even at the 60 mile QSO. 3 years ago I was doing some work for a startup company and we were using lasers to connect computers in different buildings. The system spread the beam to a 6" diameter, then recolumated it into a parallel beam. So the laser beam between buildings was 6 inches wide. First the power density was just about nothing. 2nd snow, or a bird would only block a portion of the beam. 3rd, it would help keep alignment. Yes alignment was a BIG problem. The morning sun warms the east side of the building, the then afternoon sun warms the west side, while the east side cools!!?? Amazing how much of a Hula Dance a 6 story building does! Kent WA5VJB >From owner-laser Thu Mar 28 09:16:12 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA02229; Thu, 28 Mar 96 09:16:12 PST Date: Thu, 28 Mar 96 09:16:05 PST From: jmoss (Jim Moss) Message-Id: <9603281716.AA02217@berlioz.nsc.com> To: laser Subject: Wafers as mirrors Sender: owner-laser@berlioz.nsc.com Precedence: bulk I did some experiments last night with a polished silicon wafer reflecting a 670nM laser. Found a definite signal loss in the reflected beam. Looking at the reflected image on a surface, it appears about half as bright (to my eye) when the angle is near 90 degrees thru about 2 or 3 degrees. When close to a glancing shot it is an unnoticable difference. (looks like I need to monitor some DC voltages on my RX! to quantify!) Jim WB9AJZ >From owner-laser Fri Mar 29 06:57:24 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA25834; Fri, 29 Mar 96 06:57:24 PST From: lmcpegr@langate.lmc.ericsson.se Mime-Version: 1.0 Date: Fri, 29 Mar 1996 09:40:21 -0500 Message-Id: <15c081a0@langate.lmc.ericsson.se> Subject: Silicon wafers To: laser@berlioz.nsc.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Description: cc:Mail note part Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi all, The recent discussion on using silicon wafers to reflect a laser beam prompted me to dig in my junkbox. My wafers are shiny enough, but I found that the reflection angle is critical when using it as a mirror. White light (sun) is only reflected as white at a very obtuse angle (about 140-150 degrees). All other agles will give a filtering effect, i.e. absorbing some colour. Anyway, if any of you laser buffs out there would like a sample I will be happy to send one (or a few) as long as stock lasts. The diameter of the wafer is 28mm and it is very thin, about the same thickness as two sheet of paper used in copy machines. 73 de Per, VE2/SM0DFP >From owner-laser Fri Mar 29 07:56:27 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA27039; Fri, 29 Mar 96 07:56:27 PST Message-Id: <199603291554.AA091354889@host-04.colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Fri, 29 Mar 1996 15:54:48 +0000 To: laser@berlioz.nsc.com From: "Art Allen, KY1K" Subject: flocking paper Sender: owner-laser@berlioz.nsc.com Precedence: bulk Hi Everyone, Hey, for the first time in quite awhile, I've actually thought about assembelling a complete receiving system. I've had the front end for years, and its been virtually unused-never seen anything bigger than a 1 inch f4 lens to gather light. I have a 4 inch glass lens and a 4 inch PVC tube, and the lens fits almost perfectly within the pvc, so thought I'd put it together into a system. Since it's a glass lens and the receiver is a small active area device, I'd like to assemble the whole mess with stray light rejection in mind, which means a non reflective coating inside the PVC and a long sleve in front of the lens, in order to block out light from wide angles. Yesterday, I started dubbing around with flat black paint, in a search for an alternative to flocking paper purchase. I had 2 flat black paints in stock already. Rustoleum flat black and Rutland high temp flat black were tried. I tried them both by painting the pvc directly, and also by applying the paint to verious types of paper (in varying degrees of paint thickness). Results were disapointing, at best.... -In all cases, the Rutland flat black was best!! -Anything painted directly onto the PVC is poor-even a matted coating on paper was better than painting the pvc directly. -Regarding the coating thickness on paper, the best results were obtained with minimal coating thicknesses, don't lay on a thick coat, just make it thick enuff to cover the paper. -Regarding paper type, all paper was about the same. I ried everything from newspaper up to high gloss photographic paper-no difference. -I also tried sandpaper coated with the paint, had some real coarse garnet and some fine wet/dry emery. Nothing to be gained there either, the coarse paper had big black voids, but the tops were real bright relectors-so, the average was about the same. Barb told me that, years ago, when she put her telescope together, there was a flat black paint made for this purpose, called 'ultra flat black'. I dug out her telescope and looked at its internel surface. It is a cardboard tube with the inside painted.. Well, compared to the stuff I had been dubbing with, it looked very flat!!! Unable to locate ultra flat black in local stores, but, the coating I looked at in Barbs telescope was done 15 years ago. So, if the stuff can be located, it should be FB! So, I am in need of some flocking paper-not to crazy about purchasing from Edmund, or any mail order at all due to minimum order quans. Wonder if anyone has flocking paper laying around that they would sell, or, maybe we can get a group order together and buy enuff for the entire group? I'm game for just about anything. Drop me a line and enjoy.... Dave and Merv-we should be qrv with a complete transceiver soon, wanna qso? We have easy access to Wachussett when we visit Barbs parents in MA. Per-have you been able to determine if you have line of sight to Mt Washington on the NH/Maine border? Mt Washington is hugh, and available if u make arrangements ahead of time. Unfortunately, it is snow coverered till June-and by the end of August, its snow covered again! So, the window is short, but it is a much easier drive for us to get there than the VT peak is! Let me know. Art... >From owner-laser Fri Mar 29 09:15:01 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA29159; Fri, 29 Mar 96 09:15:01 PST Date: Fri, 29 Mar 96 09:14:57 PST From: jmoss (Jim Moss) Message-Id: <9603291714.AA29145@berlioz.nsc.com> To: laser Subject: wafers as reflectors Sender: owner-laser@berlioz.nsc.com Precedence: bulk I hope to get an aluminized wafer today to re-try the experiment on reflection. Also will try a gold one later.(probably good for IR) I suspect the Oxide or Polyimide above the metals (usually there is a top layer) may cause some issues. The problem if there is no coating of course is "corrosion" of the metal. 1st wafer that I tried was Si only... no Al. Jim WB9AJZ/6 >From owner-laser Fri Mar 29 12:44:05 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA06875; Fri, 29 Mar 96 12:44:05 PST Message-Id: <199603292042.AA207982146@host-04.colby.edu> X-Sender: aballen@colby.edu X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Fri, 29 Mar 1996 20:42:27 +0000 To: laser@berlioz.nsc.com From: "Art Allen, KY1K" Subject: Silicon wafers Sender: owner-laser@berlioz.nsc.com Precedence: bulk >From: lmcpegr@langate.lmc.ericsson.se >Date: Fri, 29 Mar 1996 09:40:21 -0500 >Subject: Silicon wafers >To: laser@berlioz.nsc.com >Content-Description: cc:Mail note part >Sender: owner-laser@berlioz.nsc.com > > > Hi all, > > The recent discussion on using silicon wafers to reflect a laser beam > prompted me to dig in my junkbox. My wafers are shiny enough, but I > found that the reflection angle is critical when using it as a mirror. > White light (sun) is only reflected as white at a very obtuse angle > (about 140-150 degrees). All other agles will give a filtering effect, > i.e. absorbing some colour. > > Anyway, if any of you laser buffs out there would like a sample I will > be happy to send one (or a few) as long as stock lasts. The diameter > of the wafer is 28mm and it is very thin, about the same thickness as > two sheet of paper used in copy machines. > > 73 de Per, VE2/SM0DFP > Per, I think you will find that those AREN'T Bare wafers. The filtering effect you mention is probably due to a coating (of any number of possible types). The semiconductor process people use this 'filtering effect' to quantify and otherwise learn about the thickness/quality of the coating.. They can measure thickness of the coatings by studying which wavelengths of light are reflected and at what angles BECAUSE the coatings are so thin (relative to the wavelength) of the light. I might be wrong, but I think pure bare silicon doesnt have any 'filtering' at all. It possible the wafers might be usefull as filters actually, rather than as mirrors. Hey everyone, tonite will be the first outdoor full power field test of the new optical sighting scheme, I did add a pot to control the illumination in the homemade 'scope' here, and it looks much better in the house. Will keep u all posted regarding the results of field testing. 73...Art... >From owner-laser Fri Mar 29 15:10:27 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA11355; Fri, 29 Mar 96 15:10:27 PST From: kent.e.britain@bangate1.tek.com Date: Fri, 29 Mar 96 13:05:00 CST Message-Id: X-Priority: 3 (Normal) To: Subject: Notes from one end of the 154 mile laser record. Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-laser@berlioz.nsc.com Precedence: bulk Just got off the phone with Jim Vogler, WA7CJO. He suggests surveying corner cubes if you really want to go that route. The plastic 6 inch ones use to go for $30 and are quite bright in IR. Check in the Yellow pages under surveying equipment. On the receiver, all your equations simply fall back to capture area. A 6 inch solar cell behind a big plastic lens is far superior to a tiny photo diode and a bunch of optics. Then use Audio filters to get rid of the 120 Hz noise. The system used in the records DID NOT ATTEMPT TO IMAGE THE TRANSMITTERS! i.e. the receivers did not bring the light to a focus!! The reciever were aimed in the general direction of the other station. +/- a few degrees would not have made much difference. I've got a video tape of their work 8 years ago, got to try and dig that out. 73's Kent WA5VJB