[Laser] Ramsey kit mod
Andrew T. Flowers, K0SM
[email protected]
Tue, 11 Nov 2003 23:20:36 -0500
Gosh, that was easy.
Just remove R2--the 100K resistor after the U1A and stick the output of
the PGP font end into the empty hole that connects with C9. There you
go--now you can use your favorite photodiode with this TX/RX combonation
and gather ALL of the light your lens gives you! It gives a BIG S/N
improvement wiht my PDB-V107 (digikey) and "daylight" model front-end,
but it's hard to quantify just how much on my kitchen table. Of course,
you could just complete the RX system by making your own LP filter, but
this is an easy way to upgrade a piece of equipment you already built.
For those who haven't seen it, the K3PGP front-end and other good stuff
can be found at http://k3pgp.org
Next thing to do might be to use the built in test tone for CW mode to
make a multi-mode transmitter. It might be just as easy to make a
simple oscillator out of a 555 timer or something and throw that into
the line-input....
Andy
K0SM/2