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Philco 71 code 123 oscillator
#1

Hello all
It's been awhile since my last post.  Finally have time to get back to my7 radio bench

I am currently working on a philco model 71 code 121.
  As expected it has a bad oscillator coil

I replaced the electrolitics and brought it up monitoring the current which was within what was specified.
I put a modulated IF signal through it and all as ok.  Loud tone with volume control so everything is ok prior to a complete recapping.

I have a question as to rewinding the coil.  It’s a small winding.  Not sure where to start.  The coil wire falls apart trying to unwind it.  It is very fine wire wrapped around a cotton thread.  I have replacement wire that is close to the same size but slightly thicker.  I plan to measure the width of the winding and wrap it close to that dimension.  I doubt the frequency of the local oscillator will be correct.  Can I bring the spread in using the existing adjustments for the oscillator adjustment or will I have to start changing parts in the oscillator circuit.  Has anyone else tried this?
Thanks
 
Tom


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Messages In This Thread
Philco 71 code 123 oscillator - by tmr63 - 02-13-2024, 08:16 PM
RE: Philco 71 code 123 oscillator - by tmr63 - 02-19-2024, 09:28 PM
RE: Philco 71 code 123 oscillator - by tmr63 - 04-16-2024, 06:47 PM



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