05-11-2020, 12:16 AM
I noticed an interesting thing when looking at the alignment instructions for this radio.
I have both the Sams and the Philco service manual and the Sams instructions for FM alignment are different and do not make sense. The Sams call for tuning gang fully open
While the Philco says fully closed. Also the connection points are different and adjustment sequence per step is different. For example:
Sams step 1 (o-scope method):
connect signal generator to pin 1 of 6BA6 through .1 mfd cap
Dial setting at a point of non interference, connect scope to pin 2 of 6BC7
Adjust A10, A11, A12 and disconnect 2 mfd capacitor from pin 2 of 6BC7
Philco step 1 (only o-scope method is suggested):
Connect signal generator to pin 1 of 6AU6 through .1 mfd cap
Tuning gang fully meshed, adjust TC10 for correct crossover, TC9 for max and equal peaks
The rest of the instructions continue these discrepancies.
I am only doing AM on my radio but thought I would warn others to get the Philco instructions
If doing an alignment on a 51-1733 or 51-1734. The instructions for 51-1731 and 51-1732 may also be different between Sams and Philco.
The Sams AM instructions say tuning gang fully open, Philco says tuning gang fully meshed.
I thought this may help another member.
I have both the Sams and the Philco service manual and the Sams instructions for FM alignment are different and do not make sense. The Sams call for tuning gang fully open
While the Philco says fully closed. Also the connection points are different and adjustment sequence per step is different. For example:
Sams step 1 (o-scope method):
connect signal generator to pin 1 of 6BA6 through .1 mfd cap
Dial setting at a point of non interference, connect scope to pin 2 of 6BC7
Adjust A10, A11, A12 and disconnect 2 mfd capacitor from pin 2 of 6BC7
Philco step 1 (only o-scope method is suggested):
Connect signal generator to pin 1 of 6AU6 through .1 mfd cap
Tuning gang fully meshed, adjust TC10 for correct crossover, TC9 for max and equal peaks
The rest of the instructions continue these discrepancies.
I am only doing AM on my radio but thought I would warn others to get the Philco instructions
If doing an alignment on a 51-1733 or 51-1734. The instructions for 51-1731 and 51-1732 may also be different between Sams and Philco.
The Sams AM instructions say tuning gang fully open, Philco says tuning gang fully meshed.
I thought this may help another member.