Hello Justin With LEDs, IR is no more dangerous as with red light. You could use low cost IR LEDs SIEMENS SFH400 to try. Each LED can be supplied with 0,3 A to...
Hi, Be careful. 10 watts into a cone of 16 degrees gives power densities above 1 mW/cm^2 if you are near the diodes. With visible light you get some...
Oatley is well known on the laser list. They have a good reputation for supplying what they advertise as well. Regards, Art...
Art
KY1K@...
Oct 1, 2008 7:06 pm
305
Hello, Yves, I know you are well versed in this topic so please forgive me for saying things that are elementary to you. There may be some members of the...
VK3AFW
vk3afw@...
Oct 1, 2008 11:50 pm
306
Now you guys have me afraid of the 100 watt light bulb in my desk lamp. Rye From: Optical_DX@yahoogroups.com [mailto:Optical_DX@yahoogroups.com] On Behalf Of...
Hi Rye, Well maybe don't be scared, just be respectful. You can burn your fingers if you touch the lamp when it is on, if you stick your fingers in the live...
VK3AFW
vk3afw@...
Oct 2, 2008 12:46 am
308
Hi, You can see a list of my groups on Grouply at the link below. Maybe you'll find some you want to join. allan Here's the link: ...
Greetings All, Two nights ago Rex VK7MO/3 and David VK3HZ conducted non line of sight cloud bounce experiments in VK3. Distances of 111 and 165km were achieved...
I was looking at the r.e.as.t opto comms page and wonder where one can get a telephone hand set like this as seen at this address. Thanks in advance allan...
If you will Google "antique telephone parts" there is a retired telephone man that collects and restores old telephones there. I have purchased a few of these...
Justin, "At 165km WSJT signal levels peaked at -18dB and the elevation was found to be critical." Your experiment confirms Marius F8DO and I said at the...
Hello Yves Thank you for your comments on the gain with low scattering angle. This is an issue we have also been thinking about and it would be useful to have...
Rex All the theory is on the site : http://www.philiplaven.com/index1.html For 10 microns, the typical size of a cloud droplet, you will find the scattering...
Rex All the theory is on the site : http://www.philiplaven.com/index1.html For 10 microns, the typical size of a cloud droplet, you will find the scattering...
Hello Yves Thanks for this advice and the very useful web references. It certainly makes things much more crical for smaller drop sizes. I guess drop sizes...
The web site reference makes interesting reading. One thing that it shows that is not evident in the table of information provided by Rex is that there appears...
Well, to partially answer my own question, the visible horizon for the transmitter at 500m ASL and cloud at 3,500m ASL is 211 km. So, if the receiver was at...
Have found these simple circuts on the web , and as I have no one to experiment with, these circuts are for short distances, mainly a few feet. (meters) ...
Greetings All, Last night Rex VK7MO and Joe VK7JG went portable in Northern Tasmania from one side of the island to the other using Bass Strait as a 224km ...
... Maybe I'm not too sure: is the bandwidth really mHz (milli Hertz) or is MHz (Mega Hertz)? If it is mHz, with what kind of signal are you modulating the...
Justin, All our congratulations to the teafor this optical DX. It is not the limit and I am certain with a solid clouds layer the signal will be mutch solid...
Sorry for the previous mail sent because bad keys using :-) Justin, All our congratulations to the team for this optical DX. It is not the limit and I am...
OK, after reading the message from Yves F1AVY I recognize that the trasmission was made using Jason mode, so the bandwidth is in millihertz. . best regards _...
Hello Yves Thanks for your kind congratulations and advice on using Jason. I am playing with Jason now getting an idea how it might work. We will try it out...
Congrats on your cloudbounce achievements. I have been following you guys with great interest. Thanks for documenting your activities so well. Your hardware...
Hello Rye We are using DL4YHF's program Spectrum Lab which can be set for bandwidth down to mHz and less and also set to plot different types of data or output...
Hello Rex Good luck with "JASON". This program is may be the most sensitive communication one and it is very less dependant to soundcard frequency accuracy...
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