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With B+/- disconnected at the cap the power supply is OK. DBT acts as it should. Can I disconnect the WOA board only from the B+/- leaving the SJ2741's connected? Will it cause them issues with their base floating?

7 M ohm from collector to chassis on all 4 SJ2741

I'll check but only SJ2741's installed.

What happens if I disconnect the B+/- from the WOA board? Does it hurt anything such as the SJ2741 pre-drivers? I'm curious if the DBT will behave with it disconnected. I'm not finding any smoking guns regarding misplaced components on the WOA board.

Both B+/- fuses OK

Keep in mind that after installing the DCP and new bulk caps it was working albeit with a high offset on the left (edit) .

None. When I turn on the DBT I get a brief voltage but with in a second goes to 0. After switching off the DBT voltage is shown quickly dissapating to 0.

+/-15 is about 6 volts. No DC on the outputs as measured on the left channel input of the DCP board.

Can you disconnect the B+/- from the WOA board to see if it comes back? I checked and the 1 Amp fuses are OK

I'm confident the wires are connected to the WOA board correctly. That would leave a possible assembly error on the board. I checked and all of the electrolytes are correctly oriented. The TO220 transistors are in the right place. No diodes in backwards. :confused:

I went all the way to 120 and bulb never dimmed. While I was going to 120 I was monitoring the B+ and it never went above 8 volts. Something is a miss. Nothing seemed hot on the WOA board. The WOA power up instructions say to install the 1 Amp fuse.

I'm going to wait for some input and watch a little 3rd round action at the Masters.

I'll probably end up doing that. I'm looking at doing some DIY anodizing in black. It looks relatively simple but I'm sure there's a little trial and error.

Right now I'm monitoring both speaker outputs and the AC coming out of the variac. 1 Amp fuses in the B+/-. Only the pre-drivers installed. No speaker protect relay click as of yet. I can understand nothing on the speaker output meters since there's been no click. I measured the B voltages and...

How does the DBT react to the AC Creeping up to 60VAC on the variac? I've only ever experienced whacking on full line voltage and seeing the bright then dim. On the way to and once at 60VAC the bulb was glowing, which made me nervous so I shut down. No hot electronics smell though:)

Already taped up.

I'm ready to power things up. I've had the face plate removed this whole time. Would it hurt anything to do the power up sequences with it removed? Seems like it would be easier without it attached.

I had a little detour before powering up the 400 with the new WOA control board. While waiting for the exchange of the variac I fashioned extra cooling fins. I found 1 x 6 aluminum channel on they bay. After cutting off one edge I was left with the perfect size to become a pair of fins. I...

It's just a reflection of the edge of the trace that runs diagonally under R39L.