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Philco 89 oscillator issues
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I have been working on a Philco 89 and have issues with the oscillator (36 osc tube).  I replaced the caps and out of spec resistors, and I had to rewind the osc and detector coils.  The oscillator is running, but at a frequency of about 4.4 MHz, and does not change with adjusting the tuning cap.  I would assume that if I had wound the coil backwards (it appears to be right) that it would not even oscillate?  So far, I have not been able to find any wiring errors, so was wondering if anyone has ever had this problem?  The radio did not have any tube shields so I had to improvise with what I had until I can locate the proper ones.  
Doing a search, I ran across the thread by Ron Ramirez on converting the radio to use a 6A7 tube instead of the 36.  After reading all the horror stories about the unstable oscillators in these sets, I have been considering trying it.  What is the success rate among the ones who did this conversion?
In the meantime, I will continue to try to figure it out.  

John


Messages In This Thread
Philco 89 oscillator issues - by JohnSchw - 11-01-2020, 05:32 PM
RE: Philco 89 oscillator issues - by JohnSchw - 11-02-2020, 12:15 PM
RE: Philco 89 oscillator issues - by JohnSchw - 11-09-2020, 01:44 PM



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