some pics

[Shack]

I am getting closer.....still getting weak sound and bias goes unstable every time I find something that needs to be resoldered

[Shack]

I know its not as neat as id like .... if I need to take any other specific pics I will


Thanx

[sluckey]

bias goes unstable every time I find something that needs to be resoldered

That's not good. The turrets under the bias pot are close together. Is it possible they are actually touching?

[eleventeen]

Agree with Sluckey, you simply cannot tolerate flaky bias. You'll blow/burn stuff up. Gotta solve that.

[g-man]

Deleted

[Shack]

ill try it....even when I get bias voltages reading good....the sound has a harsh buzzy distortion and not real loud.  that bias pot seems touchy

its getting there, just a bit frustrating

[Shack]

nope,they arent touching Sluckey....bias is stable, think maybe my adjustments were too big.( I did reflow the turrets tho )

I assume that 48 volts on the V2 cathode is because I dont have a tank plugged in. Other than that, everything seems right except for the buzzy distortion and low power.

[sluckey]

I assume that 48 volts on the V2 cathode is because I dont have a tank plugged in.

No! You should only have 5 to 8 volts there.

[Shack]

ok, will figure out why thats off then

[Shack]

ok, im lost....dont know why id have 48 volts on the reverb driver  cathode then.....and I bypassed it with a jumper( the 3.3M resistor and 10 pf Cap)....still weak distorted sound. cant find any other solder joints to fix, so ill go through the whole amp for whatever....and  hope to find something,lol

[sluckey]

dont know why id have 48 volts on the reverb driver  cathode then

Do a resistance check with power off. One probe on pins 3/8 of the reverb driver. The other probe on chassis. What is the reading.

[Shack]

looks like 2.1k

[sluckey]

looks like 2.1k

Did you have one probe on the tube socket?

[Shack]

Did you have one probe on the tube socket?

Yes

So after realizing I wired up the 220k resistors in phase inverter to grids of 6V6 wrong, it sounds pretty good. I expected more headroom with the iron I chose and the tremolo is kind of weak, but overall I have made progress.

I will be getting reverb tank for it very soon and hopefully I can figure out the high cathode voltage on V2 before then....maybe I should go through and reflow everything on the board....seems to have caused me the most trouble, I did use the highlighter and verify all connections and values.

I hate seeing the flux splatters when I post pics, mscaggs and Dougs dont look that way     I will get better if wife lets me spend money on another....

[sluckey]

Tremolo will be strong after you adjust the bias. Bias voltage on pin 5 of 6V6s will probably be about -35Vdc after biasing to 70%.

[Shack]

ok,  almost there....think I may have gone the other way for tone....more current , but thats  ok


ill try and keep all my posts on this thread from now on

[Shack]

Bud, I just put it there and the tremolo was way stronger ....thank you for your input....ill ask more when my reverb tank is hooked up :)

[Shack]

ok im still gonna do the tremolo mods that mscaggs uses....while I wait on my reverb tank . Still need to order the shielded cables for reverb, not even sure I have regular RCA cables here anymore .

[Shack]

I also think, that since my PT is 310-0-310 with tons of current handling abilty, and my PV is now running at 385 or so with the GZ-34, that I may be able to use a SS rectifier even with the JJ 6V6....and still be ok. We will see

[sluckey]

What's a PV?

[Shack]

plate voltage

[Shack]

I am correct in assuming that reverb should work without footswitch?   I will try to go over entire reverb circuit on my days off and maybe rewire the socket, route one or two of the parallel connections around the socket rather than try to run all 3 across the socket. Still trying to figure out the 40 volt cathode voltage, but havent done much troubleshooting in a few days

[Shack]

  OK, so after rewiring entire V2 socket....it is alive. Not sure what was wrong there but I suspect that the grid wire wasnt soldered well on one side .

Thank you once again for the help ....and oh...can you float me a grand to make a JTM 45 Sluckey? 

Just kidding

[Shack]

This amp now sounds very good, and was a great learning experience for me.....seems I didnt know as much as I thought.

[Shack]

I cannot believe how good this thing sounds. If its loud enough to play with the band im so gutting the hot rod deluxe and making it into a tweed bassman and building Dougs revibe 

[sluckey]

Good sound. Good looks. Got the fever. Doesn't get any better! 

[Shack]

Can you tell me why it has a slight ticking kind of noise, even if it doesnt affect anything with the amp?  I know reverb and tremolo circuits dont cause it, can only hear it if not playing and only volume knob can make it louder or softer....not a big deal really

[PRR]

Does the ticking change with the Trem Speed knob?

Some amps leave the trem oscillator running and just turn-down the effect action to negligible/none. But the 'idle' trem oscillator is still swinging 300V waves, and bottoming-out on peaks. The small surge can induce "ticks" in other stages, through ground and B+ wires or through the air.

Fixing this kind of sneak-leak can be a major distraction.

If you don't notice while playing, all is well. If it ticks when the preacher is preaching, you can probably add a switch to turn-off the trem oscillator. (They leave it running because it can take many seconds to re-start, so a switch needs some forethought.) Or of course StandBy if you have it.

[Shack]

No PRR.....dont think it has anything to do with trem or reverb....and you can only hear it when there isnt any other noises going on, ...does get a bit louder if I peg the volume...but it doesnt seem to be anything to worry about.....

...now ive got 2 days straight of sitting here playing, and im thinking that if I use this PR on steroids amp, my band may have to include alot more Stevie Ray Vaughan in the mix.....it is Awesome, and ill know tomorrow if it will keep up well with a drummer and my pedalboard, but I cannot stop playing it. Wish I could build another, but I need to build me a Marshall type of amp, I seem to need both types with my playing.


I am going to convert an old SS Fender chassis into a Vibrochamp for my other guitar player, as I have the PR trannies that inspired me to build this one....I just had a year to make a few changes, so ended up not using the puny iron that I had.


Ill try to not drive Sluckey crazy with this project ...promise

[Willabe]

Does the ticking change with the Trem Speed knob?

Well, does it change with the Trem Speed knob?

No PRR.....dont think it has anything to do with trem or reverb....

Why do you think that?

[Shack]

because it doesnt change with the trem speed knob....


OK, so I just built my second amp from scratch....made them work (with alot of help)......but, still dont know why my strat with aluminum foil shielding mod done in cavity ....develops a buzz that goes away when I tap the volume knob.....but comes back periodically.

I dont think the ticking is anything, cause its barely audible and doesnt affect this AWESOME  tone.....thank you so much to all who took the time to help steer me in the right direction here....you guys are so cool.


Ill be making a new thread if I can get my other guitarist to help fund his vibrochamp :P

[Willabe]

because it doesnt change with the trem speed knob....

Ok, thank you for being clear. 

[Shack]

LOL.....actually its not an issue...love this thing.