[Laser] K3PGP PIN diode front end

[Andrew T. Flowers, K0SM]

Hi folks,

I just got my parts from mouser this afternoon, and this evening I built 
the k3pgp front end using a MPF-102 and 2N5088 as specified on his 
website (nighttime version).  I plugged the font end directly into my 
laptop's mic jack (figured it would have plenty of output w/o any amps) 
and found that it actually worked on the first try!  I was greeted with 
wonderful sound of 120Hz buzz from my lights--well it's mostly the 
lights since I can change the amplitude of the buzz with by shading the 
diode.  It's unsheilded right now, but as soon as I'm done with my soup 
I should have a container!

Now for the fun stuff.  The detector I'm using is a CLD-142 from 
Clairex.  What is this beast?  I know very little about the variations 
in photodiodes, so any help would be appreciated. Is there a better 
diode for me to be using--lower noise?  Right now I have some 11" 
fresnel lenses with a focal length of around 40" that I'd like to use as 
the "antenna."  Of course, any advice on how to make this front end 
better would be appreciated.  From what John says, it looks like the NF 
in receiver is pretty much determined by the diode, which is why I ask. 
 I'd like to hear from someone who has built one.

....and congrats to Allen and David on their DX!  Hopefully I'll get my 
first laser QSO after a some more solder fumes....

Andy K0SM/2