[Laser] K3PGP RX in charge sensitive photodetector

[F1AVYopto at aol.com]

Hello all.
The K3PGP RX gives an enormous roll off with the frequency  and in the 
"frequency domain" the FFTDSP programs are difficult to use with it  above some 
hundreds of Hertz.
But, in the "time domain", the K3PGP RX can  detect very weak low rate short 
pulses because it can act like a sensitive  charge amplifier. (Photodiode and 
input FETcapacitances effect)
Only the  rising signal edje gives the signal duration.
The slow traine to recover the  photodiode capacitance charge is not 
significant.
With the Audacity free  program you can detect and record by night :
- Far away lightings with  sometimes associated "Sprites" or "Elves"
- Meteors
- Air planes flashes  beacon
- Sats flares by optical bouncing with the sun and even with the city  lights 
 (100 or 120 Hz short pulses)
- With high gain and in a closed  aluminium box, it acts also as an silicon 
ionisation chamber and you can even  detect "pops" sound from radio activity or 
cosmic rays.
- Many others thinks  !!!
You will find a report about these properties in copying this link in you  
internet  navigator.
http://partner.oodrive.com/easyshare/wjshacc?action=view&key=L2b00ClmvN3x&isi=
261410&ci=248867&wid=29
Yves  F1AVY