The schematic indicates what looks like a black wire for b minus but in reality I believe it is a brown wire for B minus. As I will be using a 90 volt power supply would the white wires be joined to act as a jumper wire only?

It is difficult to say definitly as the cable, the switch and faded wires can confuse things.

I think this radio uses the two 45 volt batteries in series to supply both 45 volts and 90 volts to the radio. The red wire may give the 90 volt B+ plate voltages, white 45 volts B+ and the black B-. The brown appears to be filament - for the audio transformer from the A- battery terminal.

What I would do is pull all of the tubes and hook it up that way. Then check with a meter those voltages that can be checked that way against the specifications. If ok then try some tubes.

Ed.

Brian

If you are unsure hook up the A battery first. See if filaments glow. The room needs to be dark to notice filaments.

This will show that A and B battery leads aren't mixed up. You wouldn't want 90 volts connected to filaments.

Norm

:It is difficult to say definitly as the cable, the switch and faded wires can confuse things.
:
:I think this radio uses the two 45 volt batteries in series to supply both 45 volts and 90 volts to the radio. The red wire may give the 90 volt B+ plate voltages, white 45 volts B+ and the black B-. The brown appears to be filament - for the audio transformer from the A- battery terminal.
:
:What I would do is pull all of the tubes and hook it up that way. Then check with a meter those voltages that can be checked that way against the specifications. If ok then try some tubes.
:
:Ed.
:

Although very brittle and only holding on by a strand of wire, I was able to sort out the original B battery connectors for two 45v batteries, red and white for one, and another white wire and brown for the other. The schematic must be in error as it looks like black is low side for B but it is definitely the brown wire for one of the 45s. Radio works, plate voltages look right. The A battery is yellow (+) and black (-). This is different from many of my batttery radios as usually the 45s are joined by a connecting wire putting them in series which can be taken away if using a 90v supply.

:Brian
:
: If you are unsure hook up the A battery first. See if filaments glow. The room needs to be dark to notice filaments.
:
: This will show that A and B battery leads aren't mixed up. You wouldn't want 90 volts connected to filaments.
:
:Norm
:
::It is difficult to say definitly as the cable, the switch and faded wires can confuse things.
::
::I think this radio uses the two 45 volt batteries in series to supply both 45 volts and 90 volts to the radio. The red wire may give the 90 volt B+ plate voltages, white 45 volts B+ and the black B-. The brown appears to be filament - for the audio transformer from the A- battery terminal.
::
::What I would do is pull all of the tubes and hook it up that way. Then check with a meter those voltages that can be checked that way against the specifications. If ok then try some tubes.
::
::Ed.
::
: