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Phase Inverter Voltages are way off and I've run out of ideas. It's so far off I think it must be something obvious. ...Not to me though. :) I'd appreciate any ideas, I'm just looking down the same dead ends here.

All the voltages are right on except all the DC on V3 (heater voltage is right and is measurable from the tube side of the socket).

1: 286VDC
2: .5VDC
3/8: 4.9VDC
6: 285VDC
7: .5VDC

Pre/Power and PI have had multiple tube swaps with the same results. Sorry about the mess, this thing looked a little more presentable before I started swapping parts and chopsticking like a hungry chimpanzee.

Illustration of the area in question:


Pictures of the whole thing (click to embiggen):








Thanks for any input!

WTF is that thing going on at the filter cap!
Is that a bunch of resistors in parallel to get up the power rating?


Some of the joints at the PI look a bit suspect. You might consider touching them up. Have you actually measured the resistors there to make sure they actually are what they are labelled?

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http://pdfelectronics.com

It's that -and- it's modern art. I broke the ceramic one and put that there so I could keep working. It specs out pretty close though.



Will do. Yes, one of the '100's was really more like 140-something ohm and I changed that out for a closer-to-100-100 -now they're all pretty close.

Thank you!

R14 / R15 Swapped. D'oh! 470 vs. 470k

Thanks all!

Called it

Glad you found it. Those yellow vs brown bands can be hard to distinguish on the CC resistors.

_________________
http://pdfelectronics.com

Good plan to test them before you install them.Esp the 470 / 470K ones. I should note that in the manual!!

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Yeah - it's an easy mistake to make. I made a similar mistake in the reverb mixer of my BFDR clone. Took me quite a while to figure that one out!

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SG + Brit tube head = Nirvana

It's amazing how hard it is to catch one's own mistakes!



Thanks everyone,
--
bumper