From majordomo-owner@berlioz.nsc.com Mon Mar 3 15:54:07 1997 Date: Mon, 3 Mar 97 15:54:06 PST To: jmoss From: majordomo@berlioz.nsc.com Subject: Majordomo file: list 'laser' file 'laser.9610' Reply-To: majordomo@berlioz.nsc.com Content-Length: 8012 -- >From owner-laser Mon Oct 28 04:20:57 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA23136; Mon, 28 Oct 96 04:20:57 PST To: laser@berlioz.nsc.com Date: Mon, 28 Oct 1996 12:07:01 UTC Subject: hey, is the reflector still alive? Message-Id: <19961028.121719.9518.0.artky1k@juno.com> X-Mailer: Juno 1.00 X-Juno-Line-Breaks: 1-3 From: artky1k@juno.com (Art B Allen) Sender: owner-laser@berlioz.nsc.com Precedence: bulk I havent gotten anything in months, I realize we arent the most active group hi hi. But, is the refelctor still alive test test. Art, KY1K. >From owner-laser Mon Oct 28 09:23:57 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA29439; Mon, 28 Oct 96 09:23:57 PST Date: Mon, 28 Oct 96 09:23:54 PST From: jmoss (Jim Moss) Message-Id: <9610281723.AA29433@berlioz.nsc.com> To: laser Subject: LASER is lit Sender: owner-laser@berlioz.nsc.com Precedence: bulk Yes! It is alive! Hi Art and all. I've been recently working on increasing bandwidth on my RX system and developing a new aiming technique based on some input from a couple guys in SCAL. Bandwidth --------- Have started playing with modulating the laser pen at 1MHZ and 4MHZ rates. Looks like it works out at these rates. I've expanded the RX BW by changing to some IR diodes and faster opamps. Can RX 1MHz on a proto board with little problem. But must give up some of the gain available at 1KHz. Tried using the BurrBrown OPT210 at 1MHz, and it work fine with a 100K feeback resistor. It needs to be followed up with an additional gain stage to make up for the reduced gain. Haven't been able to try any distance with it yet, just across the room. Aiming ------ One of the guys in SCAL was using a scanner motor and hex-mirror to spinning in one plane, and then tweeking only the other plane. (x and y) I tried this at home over a 40 feet, and seems to work OK. The rotational speed of the scanner motor I'm using results in about a 800 Hz tone, so it is compatible with the other 800Hz stuff I've been doing. Using a disk drive motor speed controller to control the motor. Mounted laser to reflect off the spinning mirrors, and reflect off a steering mirror. Then move the steering mirror left/right (the scanning mirror is rotating such as to cause an up/down line). To the eye, this appears as a weak line across the room, even invisible at longer distances. But, to the sensor, it picks it up fine. (also to your eye, if you are in the line looking at the laser (CAUTION: power levels and all...). The advantage is that you only need to slowly sweep in ONE direction (left-right) instead of up/down and left/right, so the aiming ends up being a linear issue, insead of area. Disadvantages are 2-fold: duty cycle is lower, and the spot is distorted by the scan mirror. My scan mirror results in dot elongation up/down of about 100x(?) or more, this reduces the power level significantly. (aside: the elongation alone probably is 1 degree, so maybe don't even need to spin the scanning motor!) Because of the spot elongation, the duty cycle actually is still not to bad, but if it were really a point spot, the duty cycle would be very short at the RX. At any rate, in actual practice, this SCAL fellow tried it over a 15 mile path, and found it worked quite well. VOICE COMM ---------- Spent a couple hours playing with voice modulation, instead of my usual MCW. Simple audio amp playing into a biased transistor keying the diode. My modulation was about .1%, but fantastic fidelity! Need to rethink the biasing and loading so that I can push towards 100%. It's great to use the "baseband" RX technique, as it offers so many options. Still haven't had time to try the 115.2Kb IRDA technique. Got some of the supplies I needed, but not quite ready yet. Jim WB9AJZ/6 CM87xi Sunnyvale, CA >From owner-laser Mon Oct 28 09:54:30 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA01689; Mon, 28 Oct 96 09:54:30 PST Message-Id: <199610281754.AA23991@personal.eunet.fi> X-Sender: oh2aue@personal.eunet.fi Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Mon, 28 Oct 1996 20:43:07 +0200 To: laser@berlioz.nsc.com From: oh2aue@personal.eunet.fi (Michael Fletcher) Subject: Re: hey, is the reflector still alive? X-Mailer: Sender: owner-laser@berlioz.nsc.com Precedence: bulk To: artky1k@juno.com (Art B Allen) From: oh2aue@personal.eunet.fi (Michael Fletcher) Subject: Re: hey, is the reflector still alive? >group hi hi. But, is the refelctor still alive test test. Yeah, it's alive alright, we aren't though - man do we have work to do nowadays... I just checked out a 50 mW diode laser available through our local sales rep. Cheap, reasonable collimation and BRIGHT ! >Art, KY1K. Michael _\\///_ _ _ _ (' O O ') (_()_()_) I.O.O.F. *------------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 * * Cellular + 358 50 5505 293 2.304 GHz * * Phone + 358 0 1480 7521 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 Oct 28 12:43:24 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA07909; Mon, 28 Oct 96 12:43:24 PST Date: Mon, 28 Oct 96 12:43:20 PST From: jmoss (Jim Moss) Message-Id: <9610282043.AA07895@berlioz.nsc.com> To: laser Subject: 50mW laser Sender: owner-laser@berlioz.nsc.com Precedence: bulk Mike, How much is cheap for a 50mW? Local surplus store here selling 6mW HeNe with 120V PS for $99 (used). Jim WB9AJZ >From owner-laser Tue Oct 29 14:36:21 1996 Return-Path: Received: by berlioz.nsc.com (4.1/SMI-4.1) id AA20574; Tue, 29 Oct 96 14:36:21 PST Message-Id: <199610292231.AA08611@personal.eunet.fi> X-Sender: oh2aue@personal.eunet.fi Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Wed, 30 Oct 1996 01:20:12 +0200 To: laser@berlioz.nsc.com From: oh2aue@personal.eunet.fi (Michael Fletcher) Subject: Re: 50mW laser X-Mailer: Sender: owner-laser@berlioz.nsc.com Precedence: bulk >Mike, >How much is cheap for a 50mW? Errr. 1590 FIM, I guess it is around 350 USD. Runs at 3.0 Volts +- 0.2 Volts, wavelength 660 nm, comes with a collimation lens, but no spec on divergence, or any other scientific spec for that matter. Has a power adjustment on the side of the module. Module 38 mm long, module cylinder diameter 13.8 mm, aperture dia 3 mm. 20 mW 590 FIM 10 mW 350 FIM 5 mW 250 FIM All units also available for 633 and 650 nm. >Local surplus store here selling 6mW HeNe with 120V PS for $99 (used). >Jim >WB9AJZ Michael _\\///_ _ _ _ (' O O ') (_()_()_) I.O.O.F. *------------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 * * Cellular + 358 50 5505 293 2.304 GHz * * Phone + 358 0 1480 7521 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..... * *--------------------------------------------------*