What am I missing? Voltage doubler for DHT

[Thinker]

Hi Everyone,

I recently built this circuit: http://www.dmitrynizh.com/moondog-choke-dc-doubler-compl.gif

it's supplying 12.4 volts DC but, the filament looks pretty bright compared to the other channel that I left AC for comparison, and R2 the 0.15 ohm resistor got so hot it started to glow, which I don't understand why only one of the 0.15 resistors got hot, I believe it was the negative one. The 6B4G filament is suppose to draw 1 amp so if V = I x R then shouldn't 1 x 0.15 = 0.15 volts? and then P = I x V 0.15 volts x 1 amp equal 0.15 watts? So why is my 1 watt resistor glowing like a light bulb? I feel like I'm missing something.

 

[Thinker]

I was trying to copy this design: http://www.dmitrynizh.com/hum-moondog.htm and apply it to my 6B4G I'm thinking I messed something up

 

[s-petersen]

I would check the voltage at the tube filament, also you are supposed to drop 6v instead of 2 1/2 v
A 2a3 also draws 2.5 amps for filament current

 

[Thinker]

I would check the voltage at the tube filament, also you are supposed to drop 6v instead of 2 1/2 v
A 2a3 also draws 2.5 amps for filament current

I was wondering if that's where I screwed up, that the reduced current draw caused the circuit not to drop enough voltage. My filament transformer is center tapped, as a simply solution could I just use that instead of changing the resistor values? If I did change the resistor values would I just increase them by 2.5? And I still don't understand why the 0.15 resistor was dissipating so much power.

 

[BinaryMike]

I suggest you post the entire circuit, as built, and label it with measured voltages. Your original post isn't clear enough to eliminate guesswork.

 

[s-petersen]

well... if the center tap were grounded, it would short the doubler.It may work without the doubler, and drop the 2v of rectified 6vac (about 8v)
If you used 1/2 of the transformer and doubled it, it would be the same as using the whole transformer, with the negative effect of drawing twice the current from that half of the winding.