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Here are pictures of the Tramp Head Amp I am building. I would be interested to hear from anyone who would take a look and check for mistakes or errors in assembly. Thank you in advance!

Back Chassis Wiring I:
https://photos.app.goo.gl/TSuPTnKvF54nnTho6

Back Chassis Wiring II:
https://photos.app.goo.gl/MZ1BiRtc5FGNNxnM6

12 AX Wiring:
https://photos.app.goo.gl/3rMcuNaTL7Kp7jiw8

IMP Switch Wiring:
https://photos.app.goo.gl/bzwxn7UmMStZA1jE6

6V6 Wiring:
https://photos.app.goo.gl/4Xz93QuwiqxU2ezt9

Front Chassis Wiring:
https://photos.app.goo.gl/QFT64dSQbvXbySco7

Eyeleted Board Back:
https://photos.app.goo.gl/i8RLCAt9ZBfc5oDP8

Eyeletted Board Front – Overall:
https://photos.app.goo.gl/VKRRuwdGt5EZAyXC8

Eyeletted Board Front – Top Half: (47K resistor on its way)
https://photos.app.goo.gl/8QDXGoLgrEnVisDY6

Eyeletted Board Front – Bottom Half
https://photos.app.goo.gl/z1TFBTmq2UboXRL87

Any and all comments welcome!

Hi Dan. Welcome to the fourm!

Looks good so far!

Looks good. The 220K metal oxide you used for the plate resistor will work but wasn't there a 220K carbon film?

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

Yep... There was a 220K carbon film resistor. However, I just did not know the difference between that and a MO resistor, at the time. I do now! :-) It has been a good learning experience.

Thank you for pointing that out.

Congratulations Dan!!

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

Thank you Stephen! I am really happy that the amp is up and running and sounds so good. I really like the rich harmonics and beautiful warm sound. I play Pedal Steel Guitar and want a good clean sound... maybe with just a touch of "hair," but not much. I use an Eminence Paul Franklin 15" speaker and the Tramp sounds great through it. Man. I like this amp!

Here are my voltage readings with Tubes in...

AC Mains: Target - 120 VAC, Result is 118
B+: Target - 400 V, Result is 400 V
B+2: Target - 397, Result is 391
B+3: Target - 327, Result is 331
12 AX7 Pin 1: Target - 203, Result is 189
12 AX7 Pin 3: Target - 1.7, Result is 1.7
12 AX7 Pin 4 & 5 (heater): Target - 6.3, Result is 6.7
12 AX7 Pin 6: Target - 191, Result is 171
12 AX7 Pin 8: Target - 1.0 on, Result is 1.6 ???
6v6 Pin 1: Target - 0, Result is 0
6v6 Pin 2 & 7 (heater): Target - 6.3, Result is 6.7
6v6 Pin 3: Target - 398, Result is 394
6v6 Pin 4: Target - 395, Result is 392
6v6 Pin 8: Target - 29.6, Result is 28.9

The only outlier is with the pull on at pin 8 on the 12AX7. Any thoughts?

I will be adding the Trinity Tube driven FX loop to this Tramp build next. Stay tooned!

Dan, did you insulate the bias switch. If not keep an eye on it. Some people have reported an arcing issue running the amp at high power. That said, I've built two and though I don't play, people that do love it!

When you put in the tube buffered Fx loop definitely would like to hear your thoughts. Plan to build a Triwatt sometime soon and plan to put one in it

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"The only problem with being retired is you never get a day off"

Hi Hank! No, I did not insulate the bias switch. At one time, I DID hear a little popping when the gain was high and the amp was breaking up nicely. However, the popping stopped when the gain was down and the signal clean. I tried to replicate that to track the problem down, and it went away. Maybe the popping was the arcing you mentioned. How do I insulate the bias switch?

I have attached two pics of the FX Board Install. I just need a recommendation for the IN and the OUT wiring for the Tramp.

I pulled the heater current from the 6V6 pins. I think I understand what to do with the grounding. It is wiring the signal (from the Treble pot?) with which I need help.

As you can see, I cut the FX board up a little to make it fit. I hope that was OK. There is a good amount of clearance between the board and the power level switch. Also, I skipped the FX Loop "On / Off switch" for simplicity.

I cut the board with a small coping saw to allow for clearance around the power level switch. As a result, the second or "Return" jack needed to be soldered in at the one inch spacing option on the board. I drilled one 7/16" hole through the chassis. I removed the nuts from the jacks and fit one jack into the drilled hole. On the other jack, I applied gold liquid marker on the face of one of the jacks. That way, the ink made a mark on the face of the chassis to indicate the second drill location.

I found two other possible locations for the FX board that may not require cutting it to fit. One would require that the Jacks be accessible from the side panel of the chassis.

Front Chassis Jacks
https://photos.app.goo.gl/LnVcsJmMexHAM5dx7

FX Board Installed and partially wired
https://photos.app.goo.gl/nfiKB4AiByJFGfsr7

Dan, Check page2 of Tramp forum, read the fourth post from bottom ("OT Impedance Switch Arcing"). Arcing usually appears on the lugs of the switch, also the impedance switch on the OSD, too. I used the bigger switch in the spare hole on rear panel, but the liquid insulation seems to work also. Edit: There are other threads about the same issue in Tramp forum. I'm attaching a pic of how I did it. It's the big switch between output impedance switch and preamp socket. I see you got the head chassis, my builds were w/ combo chassis. ** My bad, bias switch NOT the problem, it's the output Xfmr impedance (load) switch that's the problem, put that in to run all 5 tubes and changed the 560 ohm cement resistor to a 1K per Coco's info on running EL34 and KT88's If you didn't put in the "load" switch, ignore my ramblings!

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"The only problem with being retired is you never get a day off"

Here is information and a couple of diagrams that answer the question about wiring up the FX loop - Provided by Stephen (in lightening fast response time, as usual!).

Disconnect wire from treble to master volume.
From treble to SEND /IN on FX. From RETURN/OUT on FX to Volume pot.
Connect GROUND on FX to Master Volume ground.

If you have RG174U coax, connect the core wires as above. Connect both shields to GROUND and ground as above.
Hopefully, you didn’t affect the board with your surgery!

The location is not ideal because it us so close to AC power and the power transformer. Curious to know how well it works!! My choice would be to put it at the opposite end, but your solution may work. You may need coax to keep the noise down.
One other thing though, you will need to connect the FX board B+ to a fixed voltage. So connect it here.

FX Wiring - B+ Location
https://photos.app.goo.gl/MGUAMjgxyFuQhe3T8
FX Wiring “In and Out”
https://photos.app.goo.gl/1B3Zy3vKaDPvRoSw6

Thanks for sharing the solution The original build guide for the buffered Fx loop just covered OSD and Triwatt IIRC

_________________
"The only problem with being retired is you never get a day off"

Awesome. Thanks for sharing.