Pigtail Neons :)

[pedja089]

That is ok, you can leave everything as is.
Zener in that mosfet have 100V breakdown voltage, so when you touch 100V...
That diode will protect transistor from both positive and negative spikes.

[Art]

Ok, thanks.
It's a software relay switch and indicators for an amplifier,
and later should be able to monitor some voltages as well.

[pedja089]

Nice project
I never got chance to play with valves...

[Art]

Thanks
Some vintage amps don't even have a clunk switch, and you're supposed to just turn it on at the power point,
and this "was" one of those.

Also, Just about every serious problem will make the transformer heat up, which could be detected for auto switch off,
but that might be too late for something, so it would be better to directly monitor some voltages,
if that doesn't present clock noise to it once shielded.

[pedja089]

Put some ferrite beads on pcb near connector on every pin except ground, also put toroid on wires. That should remove lot switching noise...

[Art]

Thanks for your help, it's not introducing noise, but will follow our advice anyway.

[Art]

My first PCB that isn't just a tagstrip or something.
Perhaps something only I can love



I'm glad it works, and since it's the 60's, it's fine to hand draw it,
and use DIL ICs and components like they did in the 60's