[Laser] LaserScatter

[Kerry Banke]

Andy - Thanks for putting together the LaserScatter program.  I'm just 
starting to look at NLOS optical communications and hope to give your 
program a try before too long. Last night I was happy to observe  a faint 
return from a 1 watt  Luxeon red LED collimated with a 4" lens pointed 
vertically in to a clear sky.  I'm modulating the LED at 355 Hz and 
receiving it with a K3PGP MPF102 front end without any  PIN detector bias 
resistor. I need to change the frequency a bit as it's fairly close to the 
six harmonic of 60 Hz which never goes away unless I cover the Rx lens. The 
Rx lens is only 1" a the moment and  I'll go ahead & move up to 4" on that 
as well.   For this first test the Tx & Rx units were only separated by 
about 100' on  opposite sides of my house.   I'm using the Spectran 
software to observe the returned signal.   The photodiode is a type SFH203 
(1mm and 10pF).  I'm hoping to work towards being able to communicate  over 
a hill between myself and another Ham a few miles away.  Keep up the good work.
  - Kerry N6IZW -