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 Optical Communications 
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Post Optical Communications
Are there any developments in this area? I remember PW having an article a few years ago, but to be honest seen nothing since.

Has anyone been able to develop something that works on FM?

If anyone doesn't know what I'm on about maybe this will help:

https://sites.google.com/site/g3xbmqrp3/optical

What got me thinking about it was sat on top of a hill that was over 1000 feet in Derbyshire and I could see the Wrekin some 50 miles away


Thu Oct 12, 2017 4:49 pm
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 Optical Communications 
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Post Re: Optical Communications
Did this last century ! but once you've cracked horizon to horizon, there's not a lot to do ;-)

.... and yes, FM !

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Paul


Thu Oct 12, 2017 5:41 pm
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 Optical Communications 
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Post Re: Optical Communications
There's been a huge amount of work on optical comms.
Several articles in Radcom.
The guys who are most involved are members of the Microwave Group.
Some quite remarkable distances have been achieved.
They frequently give talks at events.
Particularly interesting are the demonstrations relating to variable visible horizon.

A couple of links.
https://sites.google.com/site/g3xbmqrp3/optical
Look up Stuart Wisher G8CYW, he's a major player.

There are FM and SSB systems.

Cheers

Tony

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Thu Oct 12, 2017 6:09 pm
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 Optical Communications 
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Post Re: Optical Communications
G0TSG wrote:
Did this last century ! but once you've cracked horizon to horizon, there's not a lot to do ;-)

.... and yes, FM !

Me and a fellow amateur mate who were line of sight, (me in one high spot location on one side of town, he in a high rise flat the other side of town), had a voice and simple data link between us, years ago!
Albeit amplitude modulation.
R.S. used to sell an off the shelf low power laser, that had a "modulation" input wire as well as the D.C supply.
All you needed to do was supply a suitable Amplitude modulated signal to it, and voila, modulated laser light source.
But the thought of having to go up large hills and accurately point our modulated lasers at the other enterprising soul up another high spot, many more miles away, just to say "we did it", didn't really float our boat and thus, the experiment, as enjoyable and enthralling it was it was at the time, ended there!
We had read about it, made the effort and tried it, got it to work, and then thought......"well that was interesting, but it's not really radio"! :)
Doubt I will be trying it again.
Other than truly fixed unobstructed point to point, it really is quite useless and cumbersome.

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Thu Oct 12, 2017 6:32 pm
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