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Well, I plugged it in for the first time tonight just to watch the tubes warm up. The rectifier glowed, but it was the only tube. I'm posting two large images of the completed guts just in case someone might be able to help me trouble shoot. Do you guys have any ideas?

And I was wondering what the safe procedure is to work inside it now that it's had power flow through? How do I discharge the capacitors?

It has to be the heater wiring on the first tube the green twisted wires are going to, make sure that one of the greens goes to pin 4 and one to pin 5. Your brown and yellow twisted pair should then run to 4 and 5 on the next tube from there one should go to pins 4 and 5 the other to pin 9 for each of the other three tubes. I always make sure the caps are discharged by putting a meter measuring DC from the hot end of the cap to the chassis but be careful. Also make sure that you have a load on the amp whenever you fire it up otherwise you run the risk of trashing your OT.
Nigel

Yes, it has to be the first heater connection . Check there is approx 6.3 VAC across the green pair of wires.

on a further note, make sure the same colour wire goes to the same pin of all the preamp tubes. e.g. the yellow goes to pin 4&5 of all 3 12 AX7s, and the brown goes to pin 9 of the 12 ax7s. This will minimize any hum caused by out of phase heater wiring.

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

Thanks a bunch guys. I was really worried here. Nigel, what is the best way to put a load on the amp? My truck is out of commission for a few days, but hopefully I can get a multi-meter within the next few days. How will I be able to test to see if the cap is discharged?

Take a wire with Alligator clips on it, clip one end to the cap. Touch the other end to ground. That will discharge it.

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

What I meant there was always remember to have a speaker connected when you turn on an amp.
Nigel

You can use an 8-10 ohm 5- 10 watt resistor, and attach it to a 1/4" jack as a test load. Just to get things going.

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

Thank you very much, guys. I went to the local electronics store over the weekend for a multi-meter and they said they don't mind testing the voltage off those wires for me. This afternoon I plan on taking the chassis back out of the cabinet to look at those connections. I'm nervous, but only because it's an unknown thing to me. I'm confident that it will work out well, and I'm learning a lot by having to trouble shoot.

What is the procedure for testing the voltage? Do I touch the rods to the pins with or without the power on? I tried it without power and didn't get a reading. When I tried it with the power on, there was a spark and I decided to stop before asking.

You have to measure the voltage with the amp on and not on standby, I usually do this operation with one hand behind my back or in my pocket, that way if you do touch something by accident you won't be directing a current across your upper torso.

Step 1. I can't stress enough, BE VERY CAREFUL!

Step 2. I use an alligator clip on my common (black) terminal probe and connect it to the chassis.

Step 3. Set your multimeter to DC, if there are ranges of readings you need to set the meter to the appropriate range for the voltage you are expecting.

Step 4. Being cereful not to short anything, touch the live (red) probe to the point you wish to measure the voltage of.

Good Luck

Thank you very much! That's definitely not what I was doing. I was touching red to one wire, black to the other. This is all new to me. I've been building guitars for about ten years, but this is my first journey in this field.

It's a little nerve-wracking to touch the wires knowing they're live. I had my rubber gloves on and everything.

I have 3 VAC on each individual wire. I tested them individually, disconnected from the tube socket. I guess I'll solder them back to the socket to see if I still get that.

EDIT:

I soldered everything back and tested along the way. I have my 3 VAC per wire at the socket. The tube still won't warm up. I'll try to get the prong into the socket where the tube would connect to see what happens there.

Hi James0

I guess its the heater wires you are measuring, from ground to each wire
it should be 6.3/2 = 3.15 VAC +- som % and depending on the accuracy
of the multi-meter. If the measurements are taken with the tubes in place.
Without load (tubes) the value would be a little higher.

Im doing my first build (Spitfire) just got the power supply
connected up tonight. Did some measurements:

AC RMS Measurements: Input 231V
Without tubes and amp circuit.
Heater Green: 6.78V
Heater White: 6.78V
Heater Red: 5.64V
CT to Brown: 298V
CT to Brown: 298V

The voltages are high since there is no load. I had some fears about
the transformer since its input specifies 220V, but usually in norway we
got 230-240V from the wall socket. Seems that it will be ok and the voltages should drop to a suitable level once the tubes are in place.






Here's the schematic if anyone wants it:
http://home.online.no/~eber-ha/TubeAMP/schem3.jpg

Could it be the tube that has gone to tube heaven?
If you've checked and double checked that the connections match the
schematic and the voltages at the pins are correct, as it seems from your measurements, maybe its the tube?

I just checked the voltages by the tube sockets, and they're all 3ish VAC per pin. But none of my tubes are heating up? They're all new JJ's. My next check will be to see if I went the wrong direction in my counting and went to pins 5&6 instead (I'm positive I didn't).

Espen, your work looks great. It's very clean!

I'm very embarrassed to say this, but I have my pins backwards... Thank you everyone for the help.

Don't sweat it. I remember checking AC voltages on the DC setting.

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

I don't mind too much now. It's given me the chance to make the wiring much cleaner! I'm crossing my fingers for firing it up tonight.

Hey James, I just noticed my post had said set your meter to DC, I forgot you were measuring the heaters which are AC just remember when you start measuring the high voltage stuff after the rectifier you will be on DC not AC .
Nigel

Haha, no problem. I'm using the incredibly useful hi-voltage gif Stephen made for us and going by its numbers.

Well, I have power! It was incredibly gratifying to see those tubes glow, and I believe the new wiring is cleaner. So all in all, nothing but improvement.

But now I don't have sound. Would you mind letting me know if my jacks are wired backwards?

The inputs:


The outs: