[Amps] Master Voltohmyst

[Bill Turner]

This is really getting off topic, but if you would like to reduce the 
zero drift of your VTVM - any make or model - change the tube to a 
6FQ7. You will have to rewire the filament connection but that's 
minor. The 6FQ7 is pin-for-pin replacement for the 12A* series and is 
far more stable over time. It was designed as an RC type horizontal 
oscillator in the old tube type TV sets and stability was a prime 
consideration.

It is about a half inch taller than the 12A* tubes, so that may be a problem.

I've modded all my VTVMs with it and they work much better.

73, Bill W6WRT