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I.F. coil bypass - Sort of like a heart bypass
#9

Hi All;
Well I have definately found out that the 1st IF Transformer is Bad, I wired up the rest of the front end.. I applied Power (no smoke, so not all is bad), and after much probing and adjusting..
I thought to check voltages on the 1C6 and I found out why the mixer was not working.. The plate voltage was 2.xx volts,, I rechecked that I had the wires were hooked up correctly and I also had it connected to +135 volts, which I did..
So the coil is bad, and in my checking, I found the secondary is now bad as well. so, while I look for another, I will try a couple of things, One is the two resistor cap hookup.. Would a 22K on the primary (Plate side) and 100K secondary (Grid side) with a 200 pf Cap in between work OK..
Another is I have a couple of If transformers from my AA5 parts bin and I will see IF I can make one of them work with de-tuning it, from 455Khz to 460Khz..
I figure it can't hurt to try..
THANK YOU Marty


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RE: I.F. coil bypass - Sort of like a heart bypass - by marty - 07-27-2013, 06:59 PM



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