36w First powerup HELP!

[macombaland]

I have some new voltages. I used another meter and I think these are more accurate. I also found 2 places in the circuit that were not properly grounded. One was lug 1 on the clean volume pot & the other was a ground coming off of pin 2 on the el84's.(pin2---68k res.---470kres.---gnd)

I hooked my guitar up and was able to get a faint signal through, but it was very quiet and that was with the volume and master pots maxed.


V1 12ax7
1. 159v
3. 1v
6. 204v
8. 1.9v

V2 12ax7
1. 65v
3. 287v
6. 203v
7. 65v
8. 68v

V3 12ax7
1. 212v
2. 183v
3. 195v
6. 211v
7. 179.9v
8. 194.6v


V4,5
3. 17.3v
7. 259v
9. 237v

V6,7
3. 15.3v
7. 250v
9. 210v

[macombaland]

Well I haven't had any suggestions for a few days now.

Could my problem be a bad OT?

The faint signal that gets through seems to fade out after about a minute of the amp being on.

[snoof]

using your meter (DC voltage, blk to grnd, red doing the tapping), tap on the grids of the PI, do you hear a loud pop from the speaker? Tap the plates of V1, do you hear anything?

[krx]

Well I haven't had any suggestions for a few days now.

Could my problem be a bad OT?

The faint signal that gets through seems to fade out after about a minute of the amp being on.

I doubt it's the OT.

Your new voltages don't look insane like before but you still have some problems. Don't have time to go into it all now, but take a look at the voltage charts in the download section and that should point you in the right direction (i.e. which parts of the circuit you have problems in).

[macombaland]

I finally got my new rectifier. It seems to have reigned in some of the voltages and it looks like V3 is the furthest off.

Since I put in the rectifier it has started to blow the 500ma fuse off of the 0 tap of the (190-0-190). It will run for a couple minutes then will blow.

On the clean channel I can get a little more volume...on the 2nd channel I still get nothing



V1 12ax7
1. 205v
3. 1.4v
6. 299v
8. 3.39v

V2 12ax7
1. 91.7v
3. .8v
6. 313v
7. 92.6v
8. 95v

V3 12ax7
1. 309v
2. 283v
3. 299v
6. 313v
7. 281v
8. 291v


V4,5
3. 11.59v
7. 350v
9. 320v

V6,7
3. 11.5v
7. 360v
9. 340v

[snoof]

Assuming that you have the right fuse installed, something is pulling too much current. V3 p2,3,7,and 8 are way high according to the 36w voltage chart. you need to stare at V3's wiring for a while and make sure it's all good. Use the continuity setting on your meter to make sure grounds are solid etc., and that there isn't cont to grnd where there isn't supposed to be (B+ feed?). Check the filter cap feeding V3 as well. Pics are the way to go here man, worth a thousand words as they say. PI's can be tricky, so just go through the crkt one at a time and check it all.