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Here are the measurements with tubes in.

VRM idle VRM max
Cap 1 2.6 47
Cap 2 462 456

29 .169 2.89
340 2.4 42.5
191 1.9 30.3
203 2.2 34.8

Main voltage at fuse holder: 64

Heater voltages
Power tube: pin 2&7 : 3.5
Preamp tube: pin 4&9 : 3.5

If your main voltage is only 64, that's the first place to start. It should be 120V, same as at the wall.

Is it possible I can still have a grounding issue?

Well, at this point I think I'll be taking out the board so I can also check the bottom and spend more time cleaning up the solder joints and making sure all the right connections are in place.

Thanks again for the help Andrew.

I'm assuming you are in North America....

If it were me - and again I am Really not very knowledgeable - I'd probably spend some time getting the main voltage where it needs to be before taking anything apart.

Micheal, is your meter working properly?

Did you have it set for AC volts when you checked the line voltage at the fuse holder?

What does your meter read if you set it for AC volts and measure across the black and white wires on the power cord?

What does it read if you (carefully) plug the probes directly into the wall socket that powers the amp?

Thanks Mitch, I'll be away this weekend and will try that
.
Andrew, I live in Ottawa.

Good advice. The outlet could be miswired as well. Check that too.

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

Is that 64V voltage coming 'out' or going 'in' to the fuse holder? Very strange, as everything is half the line voltage.

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

it's 64V for both. This is with the black to chassis and the red at the 'in' or 'out'.

Can you post a good picture of your power side wiring?

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

Thanks for taking a look Stephen.

in picture 3, showing the connections to the power switch, is there 124V between the switch terminal and the 3-lug terminal strip? there should be.

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

Yes, it's 124V from the switch terminal to the 3-lug strip.

And what is coming out is half what was expected. If you are getting only half of the expected voltage out, It seems like the Wires to the transformer are labelled wrong. From the picture you posted, they look correctly connected according to the wiring diagram and layout.

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

What are my options? Reverse the wiring from the transformer?

Looking at your first post, it looks like you have a high enough B+. I was thinking it was half because your heater voltage was half. Is your heater voltage, in AC volts, 3.2 across the heater or 3.2 from each pin to ground, totalling 6.4 VAC?

In summary, what is your B+ on max and what are your heater voltages.

Thransformer wiring may not be the issue!

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

Meter set to AC
Measurement - pin to ground
Power tube: pin 2&7: 3.5 AC
Preamp tube: pin 4&9 : 3.5 AC
Measurement - pin to pin
Power tube: pin 2 to 7: 7.0 AC
Preamp tube: pin 4 to 9: 7.0 AC

B+
-----------------VRM idle----VRM max
1st 50uf cap:-----2.6----------47
2nd 50uf cap:-----462--------456

To supplement my lack of knowledge with measuring, I'm having a friend over Friday after work that has a background in hardware/meters/circuit boards, so he should be able to help figure this out. I've promised beer after it works.

Again, I appreciate it all the help.
Michael

Interested to know how it works out! Beer should get the job done.

In the meantime, trace out all your circuits, comparing to the schematic. Make sure everything is where it is supposed to be.

G'day Michael,

Probably stating the obvious but those VRM voltages look very weird to me (also, for clarification are you calling C12 "1st"?. Just pointing this out because the "first" cap is actually the second cap in from the end of the board (C13) which is connected directly to rectifier diodes, hence "first").

It's hard to tell from the pics where the connections go as they seem to be under the board but it might be worth double checking the VRM control pot to board connections for correct point to point routing and also soldering/connection quality.

For example, on an amp with tubes in and speaker connected, I'd expect readings more like:
VRM B+ measured at positive side of C12 =
Position Idle = 40 VDC
Position MAX = 427 VDC