On a totally unrelated note, I cascaded two preamps to get 40 dB of gain about 30 years ago. They were identical circuits, both using MGF-1202 GaAs FETs.
The input was a Zener diode noise generator. The second preamp fed a 3dB splitter which fed two inputs of a low-loss passive nulling circuit I designed. The output of that fed a 2m to 10m RX converter, which fed 10 meter receivers. That nulling circuit nulled all of that noise, much to our delight. But it's not practical on 160m. :-) And the preamps' piston trimmers could be adjusted either for maximum gain or for lowest NF, but NOT at the same setting. 73, Mike www.w0btu.com _________________ Topband Reflector Archives - http://www.contesting.com/_topband
