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Yeah, one good shock and that was all the education I need.

Ok, rectifier is on. Heater wires voltage is constant a 6.3 all the way across. I went to check the plate voltages I would assume this is pins 1 &6 on the pre tubes) and I'm not registering anything. Well to be honest my meter jumps around a bit but it's not anywhere near what you'd expect.

I also checked the 5v heater wires. They register 5.3v together. I'm not getting any voltage across the cap though. Well, I get a reading but starts low and then disapates sort of like you'd expect when the cap was discharging. Shouldn't I be expecting some high voltages when I measure from the ground to the + terminal of the first cap?

I'm not sure how to proceed. Do I need the power and pre tubes in before I get any measurement for the voltage?

What's the B+ with no tubes in. If its in the 400 range w/o tubes, go for it.

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

I'm about 408 on the B+. Sorry I was measuring VAC and not VDC before.

I'm going to through the tubes in and see what happens. I built a speaker load out of a speaker jack and a 8ohm 25 watt resistor. I would assume that will be ok.

Ok fired it up with tubes and everything and everything seemed to be fine. Seemed quiet, almost too quiet. I then measured the voltages which are notated below. When I plugged in a guitar the tone was quite overdriven no matter where I set the volume and master. (it actually sounded quite good!) The volume was also very low no matter how much I turned it up although it did attentuate slightly from silent to full on volume. Of course the overdrive increased in gain as I turned things up. To sum up I have an amp that isn't loud as all but what sound it has is quite overdriven. Think AC/DC type overdrive.

Here are the voltages:

Pin| 1 2 3 4 5 6 7 8 9
---+---------------------------------------------
V1 |141 -- 1.40 -- -- 141 -- -- --
V2 |165 -- 1.20 -- -- 276 165 -- --
V3 |259 -- 69.1 -- -- 246 43 -- --
V4 | -- -- 7.6 -- -- -- 360 -- 231
V5 | -- -- 7.6 -- -- -- 360 -- 231
V6 | -- -- -- -- -- -- 360 --

Sound is a good start. You are in the ballpark.. Your B+ is 360 VDC then.

Summary of voltages: 276 hi 259 hi 43 lo so check the resistor values feeding those pins i..e make sure the color code is correct.

Also compare to the other 15 voltages that have been posted.

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

Well, I went around checking resistors. The ones hooked to my high voltages seemed ok. However, I checked every resistor and found some interesting things. None of my 220k resistors are even close to correct. I couldn't even get a reading on one of them. Also had a couple of 100k's that weren't close. I will head over to the local electronics place and see if I can pick up some replacements in the morning.

How far out are they? Should be within +/- 10% max.

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

Well, one of the 220k doesn't even register. The others are all under 100k.

Maybe it's broken or cracked. Give it a wiggle, measure, pull it out of the circuit & re-test.

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

Ok, I went and got some new resistors. One was definitely dead. When I pulled the others I found out something interesting. When I pulled them they measured within tolerances. When I put them back in they didn't. The following two pics illustrate what I mean. Do you have any idea why resistors measure strange when installed and are fine when they are pulled?

Just remeasured the voltages. I'm not sure what you meant by the 15 other voltages in your previous post. If these aren't everything let me know what I need to measure

Here you go:

Other components around them can affect their 'in circuit' resistance.

Voltages look good. How does it sound??

Voltage Check posted at:
viewtopic.php?t=151

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

Ok good to know about the resistance.

The amp is has very little volume and goes from heavy overdrive (where it should be clean) to outright distortion as you turn up the volume and master. The loudest it will go could be descrived as a small transistor radio on one.

Any ideas on the volume and distortion issues?

Can you sub one tube at a time. They have been known to go bad

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

Would you say this is likely to be a preamp problem or power amp? I don't have any EL84's laying around but I can pull some 12ax7's out of one of my other amps.

Bad tube.

I can't turn it up much because past ten and I live in a condo but it sounds friggin' sweet. Tomorrow when my neighbors go to work (I work at home most of the time) I will crank it and see how it really sounds.

It's going to be even better when I build my cab. Right now I'm running it through a Peavey Classic 112 extension cabinet. I don't even know what it's loaded with.

Thank you so much Stephen!

Fantastic News! You're welcome.

The voltages are probably in line even more now. Can you remeasure and post them for reference? [maybe in the post I sent out]. Then you know what your working 15 is in case you have to troubleshoot again.
Now you also know what a bad tube sounds like.

Which tube was it? And how did you figure it out?

If you can resist playing it the final suggestion I have is to trim excess wire off longer leads, tie wrap some of the power leads together. Just housekeeping really.

Then put it in a cab and start to build your next amp

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