10-22-2008, 06:56 AM
Hi
a 643-A is a 643 with an extra ballast tube connected in the filament circuit.
As for 643B, the B = Baby Grand (in your case, a tombstone style cabinet).
You need the schematic for the radio to figure out the various pins on the battery plug. The two extra wires are, most likely, for the "A" (filament) supply. I do not have my schematics next to me so am going from memory. YMMV.
a 643-A is a 643 with an extra ballast tube connected in the filament circuit.
As for 643B, the B = Baby Grand (in your case, a tombstone style cabinet).
You need the schematic for the radio to figure out the various pins on the battery plug. The two extra wires are, most likely, for the "A" (filament) supply. I do not have my schematics next to me so am going from memory. YMMV.
--
Ron Ramirez
Ferdinand IN
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