[Amps] input/output transformer switching

[Steve Thompson]

>>Kill a MRF141G in the experimenting and it's a big hole in your pocket.
> 
> You have that right, I alreayd killed my one sample, so had to pay for the 
> replacement.   I know why it died, so I hopefully won't repeat that.

I've just noticed the prices Henry are selling for on ebay. It's 
not as big a hole as it used to be. I think I paid close on $500 
for the first one I bought years ago.

One thing with fets that's sometimes missed in designs - always 
have some dc path from gate to ground. A 100k resistor at the 
transistor is what I usually use. Then, if the bias supply is open 
for any reason it should survive. When learning I lost transistors 
to bias pots with intermittent contacts, or ones without endstops 
which go open for part of the rotation.

Steve