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37-660 Alignment Issue
#1

Well I've rewound the OT and it works fine. Began the alignment and all was going fine until the last SW tuning range 2 (2.3-7.4 mc). The first part of this stage you peak at 7 mc by adjusting the oscillator (30B)(no problem) and then you are to go to 2.35mc (closing the tuning cap plates) and peak there (30C) where I don't hear the sig gen signal.

If I set the sig gen to 6 mc the radio dial has to be set to about 6.65 mc to hear the tone (this is after peaking at 7 mc). To me it seems like it is short on capacitance. I note that across 30C (the 2.5 mc osc trim) there is what appears to be a large mica. According to the schematic this is 30x and is a 1150 uufd (I didn't change this one). The parts list does not say it is mica whereas it does state other small ones as mica. I am wondering if this cap might not be mica and could be causing my problem? Looking to you experts for help and suggestions.

http://www.nostalgiaair.org/PagesByModel...013220.pdf


Messages In This Thread
37-660 Alignment Issue - by marv - 04-26-2012, 07:10 PM
RE: 37-660 Alignment Issue - by TA Forbes - 04-26-2012, 08:09 PM
RE: 37-660 Alignment Issue - by LASJayhawk - 04-27-2012, 12:04 AM
RE: 37-660 Alignment Issue - by marv - 05-09-2012, 02:37 PM



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