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Question for B+ in Simple SE

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Hi to all.
I just built a Simple SE amp with EL34 ,12AT7 and 5U4G tubes.The power transformer has a high voltage secondary of 700 (680V with multimeter, (223VAC primary)) and 180mA.Although the voltage after rectifier (after c1) is 438 VDC when i check with a multimeter the voltage on c2 i get 348VDC.I use a choke 10H 150 Ohm, 180mA and a supplementary cap 1uF 630V.I dont know why there is so big voltage drop.What can i check to find where is the problem?
Thank you.
 
With power off, double-check the resistance on that choke. Or, you may have some leakage in C2? Or the supplementary cap 1uF/630V? To test this, remove those caps one-by-one from the circuit while measuring the voltage at the 'cold side' of the choke. This is rare, but, there could be a high-resistance fault in the choke? With power on, measure from B- to the case or core.
 
Either something is not wired correctly or there is something wrong with that choke. For the C2 cap to eat that much current, I would expect it to explode and it doesn't sound like your power transformer could ever supply that much current anyway.

Are you using two meters to take this measurement? If so, have you tried swapping the meters? I assume you are using the same ground reference for both measurements?

If you have a 5W or larger power resistor in the 100-150 ohm range, try swapping it for the choke. Then measure the voltage directly across the resistor.
 
A 90-volt drop across 130 ohms would be a 62-watt dissipation! (P=e^2/r) That choke would be rather warm if it were dissipating 62 watts. So, assuming it's not, methinks that 438V measurement is wrong. Is this a full-wave or half-wave rectifier? Your meter may not be measuring correctly because of significant AC mixed with the DC at C1. Try and measure the DC current between C1 and the choke or C2 and the choke. (You'll have to break the circuit and insert your ammeter in series.) Or, if you can measure the total AC current this baby is drawing, do that first. That would give you a quick reality check.
Oh, did you check to see if the choke is leaky? If it's isolated from the chassis, just measure the DCV from B- to the choke core.
 
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