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hi all,
New poster and new amp builder here. I just finished wiring up my TC15 kit, with much great assistance from Stephen along the way and lots of dipping into the forum archives. It's been a blast and a great distraction from accumulating chores.

Anyway, I'm hoping it's almost there, but it's not quite there yet. The B+ reading and readings for V1, V4, V5, V6, and V7 are all pretty close (+/- 3%) to what's given in the build guide, but V2 and V3 are way off:

V2:
pin 1: -.98
pin 3: 26
pin 6: -.90
pin 8: 25

V3:
pin 1: -.92
pin 3: 0.9
pin 6: -.96
pin 8: 0.5

I'm following Stephen's advice and going back and checking connections, etc., and hope to stumble on something embarrassingly obvious! (If it's more complicated than that, I may not be able to find it OR fix it!) But thought I'd share this info and some pics (below) in the meantime. (Some of the wire colors I chose and the angles of the photos produce strange effects in a few of the pictures, like where it looks as if the impedance switch is wired to a tube socket--at the very least, I know that's not the issue...) Thanks!

Hi

Looks like you did a good neat job with the wiring.

V2 and V3 are not getting their B+, though. Make sure all the jumpers are in place on the bottom of the board and the solder joints are good. Pay special attention to the jumper that runs between the three 22K resistors on the left side of the board (near the three 22uF capacitors) and the two 22K resistors near the center of the board. This is the jumper that feeds B+ to V2 and V3.

Use your volt meter to trace the B+ as it starts at the Standby switch then travels across the board and out to the tube sockets. See where it stops. You should be able to get high voltage readings right to the anode pins on all the tube sockets.

Thanks--will do! Will report back. In the meantime, I couldn't resist plugging in to see what was happening with channel 1, and it sounds great!

Good advice mitch. Yes trace back and see what the voltages are along the chain, pay particular attention to where the jumpers should be on the chain to plates of V2&V3

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

We're in business! As mitch suspected, it was the jumper between the two groups of 22K resistors that had come loose. With a new wire in place, voltages for V2 and V3 look to be in the ballpark:

V2:
pin 1: 154
pin 3: 1.39
pin 6: 154
pin 8: 1.39

V3:
pin 1: 164
pin 3: 1.29
pin 6: 276
pin 8: 164

And most important: there is sweet, sweet sound. Thanks again!

Great. Now a little clean up on that stray wire is in order!

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

Glad you got your amp working. It was an easy fix, but I wouldn't say the problem was embarrassingly obvious. Troubles with jumpers on the bottom of the board are hard to see. The voltage readings gave it away, though. Sometimes trouble shooting is easy.

Hope you enjoy your amp for years to come.