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Here are the voltages for my Tramp build. Note: V2, pin 8 29.2 Interior Chassis Pic

Please let me know if the voltages are within spec. Now onto what caused serious hum and what fixed it!

After correcting major jumper wiring and reworking the shielded cable continuity issues (Tips: 1)Cliff jack to board continuity checks can only be done with disconnected guitar cable in jack, otherwise you will get a false continuity reading from shield to signal wire. 2)Suggest using clip-on heat sink when soldering signal wire and shielding to prevent shorting them together).

After checking wiring, solder connections, tube swapping, worrying about a damaged OT (left for a short time without a load twice), etc. I tried again today and am getting guitar sound. After all the worrying, fussing and with some good luck with the OT, it came down to a shorted signal cable (some dummy who shall remain nameless ). Live and learn not to burn!

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

Hey, good to hear. Funny the things that can go wrong and you would never suspect. You have to be very careful with the shielded cable. I put a bit of heat shrink tubing around both the shielded wiring and the signal wire. The signal wire is very small and it's really easy to melt the covering that's over it so it's good to put a piece of heat shrink around that covering. The end where the stranded shielding isn't used just pull back on it, cut the shielding off and then put a piece of heat shrink tubing long enough to go over the outer covering and the signal wire covering. I've got my Tramp completed and am going over the connections again before I fire her up. I did an initial test of the power side without hooking up the high voltage ac to the board. Got 630vac output on the secondary power supply side, 7vac at the filaments. The power light came on as well.

Voltages look fine but what was the 6V6 cathode voltage? Is the mains 120 or a bit more?
If you use anything but the JJ 6V6 you need to be carfeul with the high B+.

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

Put a note in that V2, pin 8 was 29.2 VDC. Ifigured that was pretty close to the 29.6 VDC listed in chart. Mains voltage is slightly variable ranging from 120 to 123 VAC.

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

Amp is very noisy with 6V6, but dead quiet with EL34 (even with single coil PUPS). I wonder if it was because I damaged the OT when I powered up with transformer in 6V6 mode (low bias, 5K ). I was draining the caps using VRM with no line power and forgot to turn VRM off when I powered the amp back up (twice for about a minute each time). Must have subconsciously wanted to buy an OT from Coco. Is this a possible cause for the noisy 6V6 ? PS: Coco, you were right, Tramp sounds great w/ EL34 and my guitar playing friend agrees!

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

A bad OT would not (normally) add noise. Bad tube perhaps?

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

Will check that, got new tubes coming from Antique Electronic Supply/ Amplified Parts (pretty much the same company, at least they have the same physical address). Thanks for the quick response and easing my worries! And again, the EL34 sounds sweet in the Tramp.

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

Did you use the JJ included with the kit and it was redplating?

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

I went with Electro-Harmonix for the 6V6 and Ruby tube for the 12AX7. Now that I've fixed the bias problem I can test out an EL34. My 6V6 was red plating Sounds pretty good with the 6V6 in it, definitely Fendery. The EL34 should give a more Marshally sound I think. I may be wrong but there are only a couple of sources for tubes and they supply everyone regardless of what it says on the tube. As long as it doesn't come from China I'm good with that.

Stephen,as for me, I used the JJ 6V6 provided and used it while I was checking out the Tramp. Had various problems(no sound, leaving the amp on with no load) Once I got it running, took it to my friend Gary's (he can actually play, unlike me). Using the 6V6 had hum and some buzz, we shut it off, let the tubes cool and put in the EL 34. All the noise disappeared and sounded excellent Have ordered some more tube from Amplified Parts/AES should be here tomorrow. Hope to get them before I go to Gary's, he's having a couple other players come over and want to test amp with a new 6V6 per Coco's suggestion. Mine didn't redplate, but T-Bone's did. I'm glad he solved that problem. BTW, Gary the guitarist really likes the Tramp.

T-Bone, you're right. EH, Sovtek, Tungsol and Mullard reissue all made at the old Svetlana factory by New Sensor corp. JJ's in Slovak Republic and I think Tube Amp Doctor is out of Germany (I don't know if they manufacture or just cherry pick and re brand). I definitely avoid Chinese tubes, too ,the quality seems pretty spotty

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

Corrections:TAD - German made, EH- New Sensor and cherry picked, Valve Art and Ruby(I think)-China, Groove Tubes - various mfrs., rated and re branded. Uh-oh, I think I'm getting a little OCD here

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