I'm restoring a '47 Philco radio/phono console. The field core magnet
speaker is missing. Replaced with a similar vintage perm mag speaker,
and tried to use a power ***in place of the field core. I got 120
cycle hum. I finally replaced the ***with a 500 ohm, 20 watt
resistor. Is this about right? It is after the 5AZ4 rectifier, and
before the screen grids of the 6K6 push-pull outputs. This set uses
Philco 8-pin Locktal tubes, some of which when tested, seem to be soft,
and emission is low. Are these harder to come by than regular octals?
The set is a 47-1227, AM and FM. The phono unit looks to be in good
shape, though untested. Anybody have any ideas for me on restoring this
grand old radio?
Joe Piazza, N2MSG