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40-201 Output Xfmr Issues
#16

I found and corrected the problem I discovered as I was attempting IF alignment. I had the 1st. IF transformer secondary and tertiary windings swapped. I found it doing an ohm meter check. The secondary winding has about an 8-10 ohm resistance and the tertiary winding has less than 0.1 ohms resistance. I connected them to the correct points and the set quickly came into alignment. I found that with just this portion of alignment done, I already am getting signals on all bands and the push-buttons work but need adjusting for some local stations. This radio lives again!

Tomorrow or so I will get around to doing a complete alignment. For now I am happy. Christmas came early here!

Merry Christmas and a Happy, Healty and Prosperous New Year!

Joe
#17

As a followup to the output transformer installation and circuitry corrections, I installed the loop antenna, chassis and speaker in its cabinet yesterday. My evaluation of the unit is that although it has good sensitivity on all bands, the bass response of the replacement audio output transformer is woefully inadequate. It is only moderately better than a table model with a 4-5 inch speaker. I suspect that the original owner was very disappointed when he got his radio back from repair when the original transformer failed and had to be replaced. I plan to continue searching for either an original Philco transformer or find a better replacement with more iron in it. I had my misgivings about the replacement transformer the first time I spotted it.

Joe
#18

The hacked set is worse than a mouse home in the barn. Please post schematic or link so we can get started.




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