The RCA WV-98C Senior Voltohmyst (SN 201001 1104)I picked up at the hamfest yesterday looks to be in pretty good working order.
No smoke, popping or other unusual sounds/odours when I plugged it in. Some initial testing with batteries and some resistors suggests a bit of recalibration or maybe a bit of repair might be needed though.
Fortunately I was able to find a manual for it at the Boat Anchor Manual Archive.
Removing four screws from the back lets you take the back cover off (a fairly substantial chunk of cast aluminum) revealing the innards of the meter.
The blue adjustment screws are trim pots used for adjusting the meter calibration.
One thing that surprised me was the presence of a soldered in D cell.
No idea what vintage the battery is or what it’s used for (at the moment), but my multi-meter showed it still had 1.4 V across it. The battery has definitely seen better days. I think I’ll see about replacing the battery with a battery holder so it can be removed and replaced in the future. Fortunately it looks like the wires have enough slack to work with.
The rest of the meter looks to be in pretty decent shape, and pretty clean. Without taking off the face of the meter, it’s a little hard to get in there to check out the middle. There are two tubes in the unit, a 12AU7 and 6AL5.
Lots of colourful wires at the range selector and mode selector switches.
The probe for the meter is a big chunky thing, about the size of a Sharpie marker.
Next step will be to go through the manual and read a bit more about the meter works before I try to dive in and replace things.