Low voltage. Help!?

[guitarpkr76]

Hey guys. I just finished up a Ceriatone OTS HRM with Classictone transformers. I'm trying to work out a few kinks. The main one being the overdrive volume is way low and sounds like crap. I started checking voltage s and noticed that pin 1 on V2 was way low. Here's what I'm getting on V2:

Pin 1: 90
Pin 3: 3.8
Pin 6: 224.5
Pin 8: 1.7

Can you guys point me in the right direction on what to check? I'm relatively ignorant when it comes to this. I've only built one other amp before. So explain it to me like a 5th grader. Thanks for any help!

-Brent

[martin manning]

Check the voltage on pin 2 (should be zero), and verify the value of the cathode resistor connected from pin 3 to ground is correct.

[guitarpkr76]

Ok, it looks like the tube I had in V2 had an issue. I swapped it out now I'm getting the voltages below. The amp still sounds horrible. Not a lot of volume on the drive channel and it sound nasty and fizzy. Any help?


V1

Pin 1: 207V
Pin 3: 2.04V
Pin 6: 210
Pin 8: 1.95V

V2

Pin 1: 214.4V
Pin 3: 2.03V
Pin 6: 217V
Pin 8: 2V

V3

Pin 1: 184V
Pin 3: 86V
Pin 6: 373V
Pin 8: 86V

[guitarpkr76]

Check the voltage on pin 2 (should be zero), and verify the value of the cathode resistor connected from pin 3 to ground is correct.

Thanks for the help Martin. Any ideas with the updated voltages?

[martin manning]

V3 pin 1 is low and 6 is high; these should be close and ~300V. Something wrong there... Is that tube good?

[guitarpkr76]

V3 pin 1 is low and 6 is high; these should be close and ~300V. Something wrong there... Is that tube good?

I'm not so sure anymore. I'll check and write back. Might be tomorrow before I can get around to it though. Thanks again for the help!

[Structo]

Make sure you have the right cathode resistor paired with the correct plate.

In other words, the 220K plate should pair with the 3K3 cathode.

I had these backwards on my build and it sounded like you describe.

[guitarpkr76]

Make sure you have the right cathode resistor paired with the correct plate.

In other words, the 220K plate should pair with the 3K3 cathode.

I had these backwards on my build and it sounded like you describe.

Thanks, Structo! I'll check that.

[glasman]

V3
Pin 1: 184V
Pin 3: 86V
Pin 6: 373V
Pin 8: 86V

What is your supply to the top of the plate resistors. I am guessing the connection at pin 7 is bad or the junction of the 1M's , 820 and 24K is bad.

Also 3/8 are TOO HIGH. Normally about 55 to 60 volts.

Good be a bad tube, or one of the above.

Gary

[glasman]

V3
Pin 1: 184V
Pin 3: 86V
Pin 6: 373V
Pin 8: 86V

What is your supply to the top of the plate resistors. I am guessing the connection at pin 7 is bad or the junction of the 1M's , 820 and 24K is bad.

Also 3/8 are TOO HIGH. Normally about 55 to 60 volts.

Good be a bad tube, or one of the above.

Gary

Also be sure that both filaments are lighting up. No filament no current....