trinityamps.com

Yes, Yes, looking good!

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

So I measured the voltages without killing myself, which is good.

They're a little weird - high in some spots but mostly low across the board with V3 being the lowest and V6 being the highest. I pre-measured all my resistors and they were all within 5 per cent of stated values.

AC mains - 120 VAC

B+ - No tubes - This was weird - it read 440 to start and then dropped like an elevator each time I tried to measure it.

B+ - Tubes installed - 352 VDC

V1
Pin 1 - 161
Pin 3 - 1.33
Pin 6 - 137.5
Pin 8 - .991

V2
Pin 1 - 161.5
Pin 3 - 1.35
Pin 6 - 260
Pin 8 - 165

V3
Pin 1 - 205
Pin 2 - 33.3
Pin 3 - 66.1
Pin 6 - 195
Pin 7 - 30.8
Pin 8 - 66

V4
Pin 3 - 10.67
Pin 7 - 340
Pin 9 - 328

V5
Pin 3 - 13
Pin 7 - 338
Pin 9 - 327

V6
Pin 1 - 310
Pin 3 - 423
Pin 7 - 310

So what now? Should I give it a try with my guitar?

*sigh*

No volume on either high channel and tremendous hiss/buzz on both low channels (but I can hear the guitar fine and it sounds nice).

Before I powered it up, I tripled checked all my connections for continuity and I measured all the ground points (every one 1 ohm or less).

Time to troubleshoot I guess.

Freaking disappointing though when you go through the trouble of taking your time and triple checking.

My continuity reader is showing a good connection at each of the input jack connections.

The buzz on the working low channels gets louder when I turn up the volume and louder when I touch the strings or the guitar cord jacks.

So my brilliant intuition tells me if there is no sound from the high inputs and bad humming from the low inputs but there is good continuity on all points there must be an issue at V1.

Here is a picture of V1:



And the complete build:



I'll try the obvious first - swapping out V1's 12AX7.

Swapped out V1 tube. Status quo.

I cranked the T/V channel and it sounds wicked! But the underlying hiss fatigued my ears after one minute of power chords.

Voltages are not bad. V1 is connected correctly.

Some comments on the voltages @ V3.
V3
Pin 1 - 205
Pin 2 - 33.3 low?
Pin 3 - 66.1
Pin 6 - 195
Pin 7 - 30.8 low?
Pin 8 - 66

So check the resistors around V3

V4 & V5 - EL84 sould have same pin 3 they are tied together, correct?

Pin 3 - 10.67

V5
Pin 3 - 13


Only thing I can see immediately is the low V3.

Your getting sound on both channels but hiss & buzz.

What's it like with the guitar unplugged and the channels dimed?

Also, measure and see if there are the DC volts on the control side of the 500pf cap feeding the MV control please.

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

Hi Stephen. Thanks for the suggestions.

To clarify: I get no sound from the high input jacks on both channels with the guitar plugged in.

I get sound from the two low input jacks but hiss and buzz that gets louder when I turn up the volume and also when I touch my guitar strings. Then if I touch my guitar strings and then touch the chassis, the buzz/static goes down a bit.

With the guitar unplugged and the channels dimed there's a hum but no buzz or static (basically the sound I get from my other amps with no guitar while dimed).

And I resoldered all the connections at V1 to no avail.

The resistors off V3 are all good - 481k, 847, 480k tied into 56k.

I just re-measured V4 and 5's pin 3s - both 10.55 now.

Here are some closeups of the input jacks.

That green ground wire looks like it's on the same lug as the input wire. Is it?

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

I guess I shan't apply for a position at Trinity as a quality control officer, huh?


I'll move it to its rightful position and report back.

We have tone liftoff!!!

I grounded the high input jacks on both channels.

Moved them and I have more beautiful tone than all my other amps combined!

Thanks Stephen!

I'll have some initial thoughts up in a bit.

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

Woman will swoon and men will quake at my tone.

Looks tres nice indeed. Now, enjoy it before you start the next project.

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

I'll try to take it through its paces tonight and report back. If all goes well, I hope to have a small recording rig setup this week.

I've got a http://www.singlecoil.com order due in this week to mod my Epi Les Paul. Right now I'm running Seymour Duncans in it ('59 PAF in the neck, JB in the bridge). The singlecoil.com order is for Bumblebee clone caps and matched tone and volume pots. I'm going to wire them up according to the '50s specs: http://www.singlecoil.com/docs/paula.pdf

dear god i need a cab


BTW- Cliff jacks are where i ran into trouble too don't feel bad; they are kind of confusing to look at; you konw?

Dear Santa might work! I think he need a few weeks advance notice though!!

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

Probably not the best place to ask; but are you the best place for me to get some tubby's in USA? Or am i better off with american vendor?