check all over for shorts.. lets see. try..
filter caps
choke - if its shorted there could be way too much C on the rectifier.
the tubes could have an internal short, but if this was the case, generally a cathode resistor would go before the rectifier does, its possible you have no Rk though. (fixed bias, although even when fixed bias is used, a 10om resistor is generally put in the position of Rk, not for biasing but to check current levels easily)
just look anywhere for a short from B+ to ground.
filter caps
choke - if its shorted there could be way too much C on the rectifier.
the tubes could have an internal short, but if this was the case, generally a cathode resistor would go before the rectifier does, its possible you have no Rk though. (fixed bias, although even when fixed bias is used, a 10om resistor is generally put in the position of Rk, not for biasing but to check current levels easily)
just look anywhere for a short from B+ to ground.
Check up
I would first make sure all voltages are zero volts. Make sure the line cord is unplugged.
Unplug the rectifier (in case the tube is directly shorted).
Using a meter type ohmmeter (not digital), measure the resistance from B+, at the rectifier filament pins, to ground. Use, say, the X10k scale. The meter should go to zero and gradually return to infinity. Leave it on for 30-60 seconds. If the meter stays on zero, there is a direct short to ground. If it goes up to say, 1 meg, the capacitors are probably ok.
If the meter stays on zero, I would disconnect the power suply part about 1/2 the way down the "line" and see if the reading "jumps" off of zero. If it reads near infinity ohms, the problem is past the disconnected part. If the reading stays at zero, the problem is in the power supply section before the disconnect.
Once you find which half of the power supply is causing the problem, you can individually disconnect parts until you find the culprit.
If you want to check a choke or rectifier filament winding, disconnect both leads and measure. Use the X1 meg scale if it has one. If not, then the X100k scale. The reading should be infinity. Even if the reading is, say 1 or 10 meg to gound, I would suspect the choke or filament winding.
Also check the tube sockets, if all else fails.
Hope this helps.
I would first make sure all voltages are zero volts. Make sure the line cord is unplugged.
Unplug the rectifier (in case the tube is directly shorted).
Using a meter type ohmmeter (not digital), measure the resistance from B+, at the rectifier filament pins, to ground. Use, say, the X10k scale. The meter should go to zero and gradually return to infinity. Leave it on for 30-60 seconds. If the meter stays on zero, there is a direct short to ground. If it goes up to say, 1 meg, the capacitors are probably ok.
If the meter stays on zero, I would disconnect the power suply part about 1/2 the way down the "line" and see if the reading "jumps" off of zero. If it reads near infinity ohms, the problem is past the disconnected part. If the reading stays at zero, the problem is in the power supply section before the disconnect.
Once you find which half of the power supply is causing the problem, you can individually disconnect parts until you find the culprit.
If you want to check a choke or rectifier filament winding, disconnect both leads and measure. Use the X1 meg scale if it has one. If not, then the X100k scale. The reading should be infinity. Even if the reading is, say 1 or 10 meg to gound, I would suspect the choke or filament winding.
Also check the tube sockets, if all else fails.
Hope this helps.
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