Hi Guys Firstly my apologies if this posting is offensive to anyone or out of line. It is certainly not intended to be, and I am not selling anything or asking...
Hello, After some work, I have gotten a web page describing the 1963 effort by the EOS (Electro-Optical Systems) Amateur Radio Club to break a distance record...
Clint, Thank you for this very interesting report ! I am cherching others experiment report that could be also very intructive but I never find the initial...
I've wondered what the Aurora Borealis and other natural plasma displays _sound_ like, if detected optically. The plasma is surely modulated by the currents...
Folks, I'm building an optical receiver using an 11" Fresnel at the end of two stacked plastic buckets. http://rightime.com/images/WAAS/dscn5246a.jpg ...
Hi Tom, I'm not sure what you're trying to achieve. In particular, the role of the camera is unclear. Most of the systems used here have a Luxeon LED as...
... The detector is a PIN; the source is, at the moment, a 5mW 635nm laser, visible on top of the buckets. The initial application is rangefinding, but I'll...
Hello Tom, Following the KISS principle, I would heartily agree with Jim's suggestion of using a piece of white paper and moving it back-and-forth for the...
Clint, my crossposting on the Optical_DX group and the Laser list, and yours, raises the question: When useful discussions arise from both, what does one do?...
Actually, it looks like you responded to [Laser] here on Yahoo, Clint. In any event, there's no point in duplicating a thread, so I'll just continue it here. ...
Hi Tom, Fresnel lenses are asymetric, did you´try reversing the lens?. Regards Roger Hi Tom, Fresnel lenses are asymetric, did you´try reversing the lens? . ...
... I've read much over the last few months. I think I've read that the Fresnel serrations should be toward the sensor - and, elsewhere, that they should be...
... Could've searched that one. Easy answer to find. http://www.fresneltech.com/pdf/FresnelLenses.pdf So, apparently, my lens is oriented correctly, afterall....
Hi all, For the first time we have built an optical receiver well better the classic K3PGP RX in sensitivity in the 300 Hz to 2500 Hz bandwidth. We use an...
Hi Yves Congratulations on your new APD receiver. We would like to try it out on our cloudbounce experiments with our multi-Luxeon RED array. Can you give us...
Hi Yves, Thanks for the info on the new receiver: I've been experimenting with a new APD-based receiver as well and hope to have similar results to show soon....
... hi, congrats on your receiver! ... lightnings, camera flash, street lights, cars, good old daylight. These have *potential* to at least degrade APDs (and...
... is ... Will the ... performance. ... much ... recover ... as ... Hi all, Our APD C30817E is a very old one one (1991). It coms from an old surplus retail...
I finally had some time to do more testing with the APD front-end for my receiver and make some measurements. The APD was tested with a modified version of my...
Clint , I agree all the points you comment about your measurements. It seems to me the most of the signal SNR improvement from APDs depends of the frequency...
We have been experimenting with a 5 mm S8664 Avalanche Photo-diode (APD) and a S20 44 mm Photo-multiplier Tube (PMT) for cloudbounce. The APD uses KA7OEI...
Are you fellows using an analog modulator for your WSJT activities (like the KA7OEI circuit) or are you turning it into a digital signal and just hammering the...
... The K3PGP RX gives an enormous roll off with the frequency and in the "frequency domain" the FFTDSP programs are difficult to use with it above some ...
Hello all. Most of us uses FFTDSP programs to extract optical signals for not line of sight optical communication.(eg. cloud bounce) Another way could be to...
I am currently using a plano-convex lens to concentrate all (most) of the LED energy onto my Fresnel lens as described on several web sites. One of the locals...
Last night Rex VK7MO and Justin VK7TW achieved one way communication over a 118km non-line of sight cloud bounce path. Rex trekked to Coles Bay on VK7's East...
We congratulate the whole team on this fantastic success. We are certain this distance is not a limit. We know now that lightning storms are optically...
hello all. My name is allan egleston. I live in Sonora Clifornia U.S.A and am intirested in all forms of communication including this one. Most of the time I...
Hello Allan I have used sunlight when I was younger in an effort to duplicate Ben Franklin's Experiment where he also used, sunlight and candle light to ...
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