HELP with mainline - PSU voltage too high!

[chienbleu]

Hi, I'm all assembled and at the final voltage check, BUT getting 326v instead of 275 at the +275 pad on the PS board.

I double checked the transformer settings, voltage 120vac at 31 and 32u.
I double checked all the components/visually confirmed solder joints on the PS board.  All seems ok.
Additional Voltage Checks:
KREGs are 26 and 28v respectively
BREGs are both 0
IA is 324.8
IB is 323.6

Where do you suggest I look next?

Thx, Robert

[Doc B.]

It sounds like the tubes are not conducting. If you turn the lights down can you see the tubes glowing?

[chienbleu]

R and L tubes look good, glowing.  12AU7 was very difficult to physically insert and is just barely glowing when I turn out all the lights

I just swapped in a newer 12au7, short plate.  Getting a better glow, but voltage still 320.

[chienbleu]

SOLVED - Noticed the resistor connected to BREG wasn't in circuit to anything else.  Rechecked that part of the manual and discovered I had somehow skipped installing all the jumpers on that page! (Duh)

Getting better voltage now, but it's still only 261vdc instead of 275vdc.  Is that within tolerances?

Thanks for steering me in the right direction.

Robert
 

[Paul Birkeland]

That is plenty of voltage for the circuit to function properly.

[chienbleu]

Thanks!  Sounds GREAT!