[Laser] NLOS contact

[I]

Thanks Yves,



Your comments re the use of blue light rather than red light were very useful in reminding me that I already knew that! That is of course why I had been using red lasers and LEDs in the first place for direct contacts, for maximum range since red scatters least. I had been distracted by thought of using the 200mW red laser I have to make a very powerful concentrated beam at the scatter point.


 When we did the experiment with the strobe that gives white light, it must have been the blue light that scatters best. I wonder if that may be why the characteristic sound produced by my receiver changes from when I can see the flash from a strobe to when it is obscured, and only reaching my receiver by scatter?


 I have a powerful white LED and Fresnel lens so I might use that instead, it has a good blue content. I do not have a blue laser or power LED so this would be easiest for me to try.


Stuart G8CYW