Hue asked. so here is a copy of my original notes.
This project was born of the desire to get rid of that power wasting dual pentode that produced so much heat. (heater draws 15 watts!).
I used IRF640's which are a bit of an overkill, but I had them on hand.
Then, since the radio plate voltage is 24 volts, I figured it wouldn't be much of a stretch to replace other tubes as well.
Some I was able to get away with "drop in" replacement.
I crushed up some old computer "D" plugs to harvest the pins to use for plugging the transistors into the miniature tube sockets.
The only tube replacements that gave me problems were the RF amps because they had to work properly with the AGC.
I tried a cascode configuration with limited success but didn't work well enough. I did not try dual gate fets yet. Those will probably work.
This project was done about 4 years ago. The RF amp tubes are still there because I never got back to figuring it out.
Any suggestions?