[Laser] Recent NLOS experiments using IR Leds

[F1AVYopto at aol.com]

Very good work Kerry.
3 miles PSK31 with  perfect copy with no clouds is a very good result.
As you, we have noticed a  spherical or parabolic mirror seems quite better 
big glass lenses same  diameter.
May be it is because the IR losses in the thick glass ?
Our best  NLOS QSO (25 miles with clouds) was with a 40 cm X 40 cm focal 30 
cm thin  polycarbonate Fresnel lenses. (RXs side).
For a 7 mm² photodiode the rough  focusing of theses Fresnel lenses stays 
very acceptable.
> When sending a  pure tone the signal was about 15 dB above the noise in a 1 
Hz BW at a distance  of about 3 miles. 
With WOLF GUI at 75Hz slow mode, your NLOS com capability  in the same 
conditions seems near 30 miles ! 
73 Yves F1AVY