Next project is this VTVM.

Does anybody have any data on this unit?
A circuit would be nice.

Not used for 40 years, the battery has sicked up and rotted the chassis!
Needs a bit of TLC to get it going again.
Has a 12AU7 and a 6AL5.

I checked the web, Chant, Radio Museum, nothing on MVA-6.
Would be about 1970 build?

Did not turn it on so far, mains wiring is not acceptable and the battery acid/alkali has got into the PCB and controls.

Fred.

Probably can't be too different to other VTVM's like AWA Voltohmyst or B&K Dynamatic Voltmeter Model 375 (which I have) - their manuals are on-line.

The following website has a good summary - the site appears to be down now, but is viewable using the wayback machine.

http://tone-lizard.com/vtvms/

Hi Trobbins, yep, I downloaded a couple of circuits like the RCA "voltohmyst".
Same valves and same general switching arrangements.
The more I looked at VTVM's from different sources the more they looked alike!
I can work with the RCA circuit and just ammend it to fit the Aussie unit.

Cheers, Fred.

I used to use a V.T.V.M.
For five years at the repair shop where I was apprenticed.

Every morning. First job of the day was to warm-up
the V.T.V.M. Then put the jug on to make coffee.

After around ten minutes, the meter had warmed-up,
and I could adjust the two controls to calibrate the meter. Ohms zero, and maximum
deflection.

A great meter, but a real pain when working on transistor equipment.
imagine trying to see a 0.2 volt difference in the emitter base leads in the the small deflection difference of the pointer.
A digital display is the way to go.