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Checking B+ voltage. . . .newbie
#3

Case 1 pull the 5Y4 tube and measure the ac voltage from pin 4 to pin 6. Remember to count the pins backwards as you are looking at TOP of the socket not the bottom. Should see about 500 to 600v there. If not your power transformer is bad and you will to replace it. The lowering volume is a sign that the p/s was slowly dying from the filter cap shorting. If voltage is ok then replace the 5Y4 w/a good one and the filter caps.

Case 2 > if this guy really has no idea what he is talking about. . .
Methinks ur correct. First off measure the dc voltage from chassis gnd to pin4 of one of the 6F6 tubes. Should see a few hundred volts. Next measure the voltage from gnd to each of the 6F6 tubes on pin 3. Again should see a few hundred volts. Do likewise with pin5. Should see -10v or so there.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got it!

Terry


Messages In This Thread
RE: Checking B+ voltage. . . .newbie - by morzh - 02-21-2017, 12:30 PM
RE: Checking B+ voltage. . . .newbie - by Radioroslyn - 02-21-2017, 12:40 PM
RE: Checking B+ voltage. . . .newbie - by morzh - 02-21-2017, 02:20 PM



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