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Well I thought if I was careful enough it might just work first time....no such luck.
These are my voltages
238V AC at the fuse
VRM B+ at 400V DC

6V6
pin2 3.37VAC
pin3 400VDC
pin4 400VDV
pin7 3.38VAC
pin8 28.6VDC
all looks good

12AX7
pin1 -0.2VDC
pin3 +0.004VDC
pins 4,5 3.36VAC
pin6 -0.18VDC
pin8 +0.07 VDC
pin9 3.36VAC

both tubes are lit, and there is a very mild hum as the VRM is turned up. I cant see anything missing or shorted and am at a bit of a loss where to start.
regards
john

Check the jumper going from 47K/33uF cap to the two 100K plate resistors.
Also check the preamp ground (bottom right hand corner of the board).

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Well the resistance between those two points on the board is 0.1ohm so the jumper must be OK. Same kind of low resistance readings on all the earthed points on the board relative to the chassis. The preamp earth point is good.
thanks
John

Measure the voltage at the 47K/47uF cap and also the two 100K resistors whats the voltage (should see 340V).

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No plate voltage so work back to see where it stops. Suspect a jumper somewhere. Kurtlives is on the right track too.

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

-0.056VDC

OOOPs I think I see the problem........

OK, new voltages12AX7
pin1 180.5VDC
pin3 1.76VDC
pins 4,5 3.36VAC
pin6 166.4VDC
pin8 1.62 VDC
pin9 3.36VAC

I had attached the lead from the 33uF capacitor to the middle lug rather than the left hand lug with the two resistors on it.

Is that difference in the 180.5 VDC at pin 1 and the 166.4 VDC at pin 6 suggesting another fault to find? Its working and sounds good, though less volume than I expected, though I have only played with the VRM and the volume knobs
Thanks
John

Those voltages look fine, tube amps aren't an exact science. The two triodes inside the 12AX7 package are biased a little differently from each other so each plate will have a different voltage. You can put in another tube and you'll see the voltages move a bit more, tubes are +- 20% devices.

Give it a good play test, see how it sounds and report back. There could still be something wrong....but give it a good test first (put the MV and VRM high up and use the volume control, should be nice and loud this way).

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Pull the tude if you want it really loud

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