time to keep that glowing, my test eq oldies want to test anything sometimes.
I will start with construction of a FM radio, tubes, solding stripes, black, wires binding, same design then my audio amplifier see below
Which glowing tubes will you use Martin ?
it must not be compatible to all common tube radios.
really fascinating is a inductive mechanical tuning, but at first something to study: What is the good vs. bad of self oscillating mixer stages? Why they never used a seperated oscillator and mixer system??
There will be some breadboarding required to find a nice solution
1. system = triode (HF preamplification, selective, tuned)
2. system = mixer to 10.7 MHz (self oscillating or..
2a: oscillator
3+4: EF184 or like that, penthode IF i need a high signal level
5: FM demodulator stage, 6BN6
6: any audio, EL84 can do the job
catalog parts make me tired, means I use homebrew filters, solding stripes, coils, all selfmade.
Using sweeper, Spec, Oszi, DMM, heathkit tubes PSU, Tek130 for unknown L or C, nixie frequency counter
and a lot of junk and sheet metal.
Martin