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HQ-IV tube output balance DAC

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Quanghao, there are jumpers on the PSU board at H1 and H2 that allow you to connect the filament ground to the HV ground (H1) or to HV +70V (H2.) I understand this is to keep the voltage differential between the tubes' heaters and cathodes within spec, but none of the pictures on this thread have shown people connecting them. You mentioned it in post #209.

Is it best to connect H2?
 
latest schematic No.HV shunt

modify the values according to the latest schematic below.

thank you
 

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Is it true that you lose about 140v in the HV regulator?
I got one trafo with 240v AC
and one with 260v AC
will either of them work?

I'm using a 240V taro, and seems to work fine for me. I haven't finished the I?V board yet, but I've hooked the filament and HV transformers up to the SPU board and both work OK, i.e. I've adjusted the filament supply to 12.6V, and the HV to 220V.
 
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