10-22-2014, 11:53 PM
Very elegant solution to restore the innards of your battery. I didn't think you should solder to batteries without tabs (don't know why I thought that) so I made mine with 9 volt batteries in series for the B supply. I haven't had to replace mine in many years of light use, so yours ought to last forever with series AAAs.
Odd, but the Philco service package I obtained from Chuck Schwark seems to have contradictory specifications. First it specifies the P-41A-4G battery, which obviously produces a 61.5 volts nominal B supply. But the power specification on the same page specifies a 90 volt B supply.
I originally made my repro battery with 7 nine volt batteries in series to make 63 volts. The radio worked perfectly well. Later, when I'd bought the schematic from Chuck and saw the 90 volt specification I thought that maybe the 90 B supply in the spec would improve something, so I added 3 more 9 Volt batteries in series for 90 volts. Nothing in the radio's performance changed. I didn't make current measurements to see if that changed.
Odd, but the Philco service package I obtained from Chuck Schwark seems to have contradictory specifications. First it specifies the P-41A-4G battery, which obviously produces a 61.5 volts nominal B supply. But the power specification on the same page specifies a 90 volt B supply.
I originally made my repro battery with 7 nine volt batteries in series to make 63 volts. The radio worked perfectly well. Later, when I'd bought the schematic from Chuck and saw the 90 volt specification I thought that maybe the 90 B supply in the spec would improve something, so I added 3 more 9 Volt batteries in series for 90 volts. Nothing in the radio's performance changed. I didn't make current measurements to see if that changed.
John Honeycutt