Very high input impedance high voltage meter???

[Norm Dresner]

As a semi-final coda to this saga, I've ordered a set of three [one spare]
6SH7 tubes and I'm actively looking for a good source for the 6AV5GTs as
well. I'm also looking to pick up on eBay a non-working HP 33x distortion
analyzer or similar oscillator from which to scrounge the dual tuning
capacitors so I can make a solid state low-distortion instrument as well.

I'll also look into replacing the electrolytic capacitors.

Thanks for all of your help and suggestions

Norm

Is there any reason you couldn't gang together a pair of ordinary variable
capacitors using a gear or belt system? You could probably get away with
some cord as used in tuning dials on old analog tuned radios too.

I could also do the same thing with a pair of pots. The advantage of the
dual caps from a factory-built oscillator is that the hard mechanical work
is all done -- and they're presumably matched well enough. It's simply less
work. BTW, it's a lot easier to get 10-turn pots than even one-turn
capacitors these days..

Norm

 

[James Sweet]

I could also do the same thing with a pair of pots. The advantage of the
dual caps from a factory-built oscillator is that the hard mechanical work
is all done -- and they're presumably matched well enough. It's simply less
work. BTW, it's a lot easier to get 10-turn pots than even one-turn
capacitors these days..

Norm

Yeah, just thought there might be some particular reason you needed variable
caps.