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Philco 90 1st IF xfrmr question
#4

I tried one from a PP47 112 chassis that measured almost the same resistance- ~65 ohms both primary and secondary. It worked! But the set needs an alignment as the reception is not consistant across the dial.
This set had some wild "interpretive fixing" done on it at some point in time. I had to trace most of the wiring and in several cases re wire these fixes. Additionally, several resistors were drastically out of tolerance. The 1M ohm was reading 2 meg, and all 3 .25 meg were reading .35meg, .45meg, and .6 meg!!

The local distance switch was disconnected, and the leads of it and both 6mFd mershons were loosely twisted together.

It appears that all except one trimmer were screwed down tight. The one that was not was almost all the way out. Soooo, I adjusted them all to more or less center and did minor adjustments using strong local stations for a temporary fix once I got the set to play.

I installed the PP output xfrmr from the console speaker on the cathedral speaker I have, which was formerly for a single 47 output.


Messages In This Thread
Philco 90 1st IF xfrmr question - by TA Forbes - 03-10-2012, 01:01 AM
RE: Philco 90 1st IF xfrmr question - by TA Forbes - 03-10-2012, 11:03 PM



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