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Old 04-28-2018, 09:12 PM
Crist Rigott Crist Rigott is offline
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Join Date: Oct 2015
Location: Waxahachie, TX
Posts: 1,506
I found the problem. It was one of the Peaking coils from the Dectector stage.

Item # L188 in the RCA manual and #L119 in Sams 54-18. This Peaking coil came form the junction of another Peaking coil from the plate (pin 7) of the 6AL5 Dector and the Coupling cap #c138 (.05uf) RCA, and C50 in the Sams manual. From the junction is the bad Peaking coil, then it goes to a 3900 ohm resistor to ground.

I couldn't not fix it. I had one end, but could not locate the other. I looked up the properties (8 ohms and 250muh) and looked up a similar coil in a spare parts Motorola chassis that I have. Sure enough there was one that was 7.2 ohms and it was a "Yellow Dot" coil. I found it and clipped it out and soldered it in. Bingo!

The picture isn't all that good but it does confirm the bad coil was the problem.

Thank to all you offered help. old -tv-nut got to thinking I need to recheck those coils. That was the key.
I'm locating a replacement coil from a parts chassis that my buddy has so when I get that soldered in. I'll do a quick alignment, and declare this off my bench.

I could have sworn I checked all those coils before! Sigh......


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