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38-8 high voltage problem
#1

i have a problem hope you can help i have high voltage on these tubes
6a8 pin 3 spec 180v have 325v...
6F6 pin 3 spec 230v have 348v pin 4 spec 250v have 326v
6K7 pin 3 spec 240v have 306v
5Y4 pin 7 spec 100 have 358v
other tube pins are OK with in 10-15 volts of specs the radio plays very little distortion sounds a little tinny could be speaker has small tear

2 resistors #12 13K 10 watts & #22 51K 2 watts are getting hot,, transformer is cool and does not show any shorts I've check caps and rest for ground problems can't find any so far
can you point me in the right direction
thank
john
#2

For a starter, I'd try to measure just how much current is going through the B+ using an old-fangled ammeter. Anything over 50-75 m.a. wouold be suspect. Suba P.M. speaker and see if the audio is clear. I assume you are meauring from B- to point in question, or however the schematic you have says how to do it.
#3

i have checked to amps at # 12 13K 5 wt resistor and it read 10.56 ma so that seems OK maybe that resistor just gets warmer because its 5wt er,,,it still get a little distorted after its been on for 5 min or so still checking out the speaker is proving a bear it has a HS style speaker and you can't just put a pm in its place looking for a way to put a pm with out blowing up the radio
thank again for all the help
the old geezer
john
#4

IMO your 6F6 is gassy, or there is trouble in your cathode bios, and of course it is possible that coupling capacitor is bad. Chaiged all of 'em out?




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