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Old 19th Sep 2021, 7:33 pm   #19
mrrstrat
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Join Date: Jul 2020
Location: Rockford, Illinois, USA.
Posts: 159
Default Re: Hallicrafters SX-17 Advice on repair.

It ended top being a 10pF cap (C76 and the one coupled to it) that was drawing current and smoking my 1K resistors.

I did not have any good (new) 10pFs but lots of 6.8pF/1kV so I used them instead. Should not make a significant difference after all of the other parts are 80 years old.

Some advice here and another board helped - big thanks! Sometimes it helps to have people tell you what you don't want to hear: I was hoping that the problem was not in the coils and that subconsciously steered be toward not checking them .

I looked at the spent parts and had 5 attempts to try to measure voltage before they burned. Probably not the best idea but I have rebuilt sets before and needed to see where the voltage was dying. Some unpowered probing for resistance, loss, and continuity loss helped more than anything.
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