[R-390] Smoke got out

[Norman Ryan]

 I had a look under a spare R-390A RF deck to see what might have caused L206 to fail and noticed that my choke was touching the chassis side.  Seeing that, I bent the wires away from the chassis slightly to keep the choke from shorting.
Perhaps a similar condition in your case caused the choke to short to ground.
73Norman

    On Thursday, August 2, 2018, 1:00:34 PM EDT, dog <agfa at hughes.net> wrote:  
 
 I found what smoked, it was the 10uH choke on V205 pin 9. That explains 
all the burned wires to that point. I had to remove a whole bunch of 
stuff around that tube to find it, burned to a crisp. It's buried under 
everything. But still doesn't explain why it burned up, I must have a 
tube with a shorted filament, or I got it in wrong somehow. The 5000pf 
bypass cap measures fine. Even the capacitance measures good. I have 
some replacements, I'll change it anyhow. Now where to get a 10uH choke, 
what's the current rating on it?

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