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Philco model 70 rebuild - by Tim P.
#81

I pulled the IF coil, and much to my surprise, I found a "modern" looking coil.
   

Now, what do I do with this thing??? It doesnt look bad. I connected my meter to ohm it. It checks around 75 ohm on the primary, 55 on the secondary. I probed the wires coming from the coil to see if the resistance changed when I moved wires. Nothing. Now, interesting - as this coil warms (from my hand) it increases in resistance. I warmed it with the light bulb over my bench, and I could watch the resistance increase - to about 80+. Not sure if this means a thing or not. The secondary also did the same, just not as much or as fast. I cleaned the connections and resoldered, then reinstalled temporarily. Same problem. Seemed weaker even. I changed the IF tube again. Same. I am waiting for things to cool again and will try the ground on the trimmers. I did try tightening the bolts. I also resoldered the socket connection on the plate pin.

I did inject the signal at audio freq at the grid of the 2nd detector just to double check the AF section. Aside from a hum, it sounded ok.

I dont think I can rewind this coil myself. Any more ideas?

If I could find the place called "Somewhere", I could find "Anything" Icon_confused

Tim

Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44


Messages In This Thread
Philco model 70 rebuild - by Tim P. - by TV MAN - 01-29-2014, 11:46 AM
RE: Philco model 70 rebuild - by Tim P. - by TV MAN - 04-27-2014, 06:57 PM



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