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Restoring a Philco 71 Code 121-No sound
#16

   
After my interpretation of the schematic and physical layout, I have attempted to number the lugs on the schematic. At this point, I currently don't believe I have an open coil.

Lugs 1-3 : feedback coil (small band on the bottom outside) 7.0 ohms
Lugs 2-4 : primary with a common connection(4)  to the secondary winding 4.5 ohms
Lugs 4-5 : secondary with a common connection (4) to the primary winding 4.9 ohms

If I'm reading this correctly, the feedback coil (considered the secondary outer winding) should read 15.7 ohms but actually reads 7.0 ohms

My thought is just to rewind the feedback coil and hope for higher ohms.

Thoughts anyone would be appreciated


Messages In This Thread
RE: Restoring a Philco 71 Code 121-No sound - by dmblackburn - 07-07-2024, 09:52 AM



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