08-09-2009, 12:53 AM
Hello Gary,
Since you have the set working now, and receiving some stations, have you checked the alignment adjust using the chassis adj compensation condensers? The orig mica in them could be bad, or dirty,shorting internally? I took another look at the Riders schemat you posted originally, and the 89 has a intermediate freq of 262 khz?
If your RF gen signal goes that low, check for alignment on the compensating condensers with 1st harmonic. Or 2nd harmonic at 524 khz, or 3rd harmonic at 726 khz. Peak the compensating condensers for max vol by ear according to schematic. If you dont have a freq counter onhand to be precise on your RF gen output, a digital am dial receiver can verify your exact RF gen signal output at 262 khz by ear, listening for the harmonics carefully.Use low-output on your RF gen as possible to keep stray-harmonics low as possible.
If your main-tuning condenser is working correctly, and clean of debris,with no shorts,you should be able to tune the set fully once the chassis compensation condensers (3) properly aligned?
Read again carefully on the compensating condensers adj. for the mod 89 on Riders page 7-78.
Just tryin to help if I can, for proper alignment on your set if accidentally overlooked. Best of luck on your Philco restoration!
Since you have the set working now, and receiving some stations, have you checked the alignment adjust using the chassis adj compensation condensers? The orig mica in them could be bad, or dirty,shorting internally? I took another look at the Riders schemat you posted originally, and the 89 has a intermediate freq of 262 khz?
If your RF gen signal goes that low, check for alignment on the compensating condensers with 1st harmonic. Or 2nd harmonic at 524 khz, or 3rd harmonic at 726 khz. Peak the compensating condensers for max vol by ear according to schematic. If you dont have a freq counter onhand to be precise on your RF gen output, a digital am dial receiver can verify your exact RF gen signal output at 262 khz by ear, listening for the harmonics carefully.Use low-output on your RF gen as possible to keep stray-harmonics low as possible.
If your main-tuning condenser is working correctly, and clean of debris,with no shorts,you should be able to tune the set fully once the chassis compensation condensers (3) properly aligned?
Read again carefully on the compensating condensers adj. for the mod 89 on Riders page 7-78.
Just tryin to help if I can, for proper alignment on your set if accidentally overlooked. Best of luck on your Philco restoration!
