clare, at, snyder.on.ca wrote:

Well, I've worked on an old battery set that, like a car radio of the
time, had a multivibrator to make the high plate voltages from a lower
battery voltage. IIRC the main battery was 12 volts. Most of the
"valves" or vacuum tubes ran on either 12 volts or six (2 in series)
but the rectifier has a 1 or 2 volt filament.


I worked on hundreds of old radios in the '60s and '70s, and still
have a lot of service data. The people on news:rec.antiques.radio+phono
have a lot more.

All I have ever seen used in a car radio was the 0Z4 gas rectifier, or
a regular 6 or 12 volt filament regulator like the 6AX4 and 12AX4. A
very few used a synchronous vibrator, and eliminated the need for a
rectifier. (Till the contacts welded).


It used an "ignition"
battery - one of those that used to run doorbells, fencers, and
battery ignitions on some stationary engines years ago. It was called
the "F"ilament battery. I think it was some sort of "farm" radio.


Farm radios were 32 volts, to run of the winchargers used to charge
the batteries for lights in a farmhouse.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida