36 watt - no sound ... help

looper · Post by **looper** » Sun 07/23/06 7:30 pm

I am posting a pic and a list of my voltage readings in the hope that someone can show me where I went wrong (I hope):
V1 (1,3,6,8): 142.9, 0.844, 164.7, 1.19
V2 (1,3,6,7,8): 156.4, 1.01, 244.2, 156.4, 156.1
V3 (1,2,3,6,7,8): 208, 43, 56.5, 201, 40.3, 56.1
V4-V7 (3,7,9): 10.58, 331, 306.9

When I turn it on, the tubes glow just fine but there is no sound coming through. I used the Ceriatone 1/2 power switch layout & the board was already assembled. I am still new at this so any help would be greatly appreciated. Thanks!

Chubsman · Post by **Chubsman** » Sun 07/23/06 8:44 pm

Make sure your inputs and outputs are grounded.. that is what I always screw up on...

Getting a hum? a buzz anything....???

Double check your input sockets, make sure they are wired correctly.
Check the layout and make sure all connections are correct.

Are you getting high voltage from the transformers?

Go to the download section and find the 36w voltage chart and check that you are ok...

looper · Post by **looper** » Sun 07/23/06 9:14 pm

I am going through it all again i am sure it's something dumb I missed.No I am not getting any kind of sound at all .I got the chart and it seems my voltages are within reason I think I'm not sure whats a acceptable difference.I will just keep lookin Thanks for the reply!!!

phsyconoodler · Post by **phsyconoodler** » Mon 07/24/06 12:31 am

i usually take the layout and photocopy it on a black and white copier and use a highhlighter to follow the circuit path one wire at a time and I assure you,you will find the problem.
If it 'aint wired right it won't work.

looper · Post by **looper** » Mon 07/24/06 9:52 am

Thats a good idea i will try anything at this point thanks

brownnote · Post by **brownnote** » Mon 07/24/06 10:50 am

One thing you can do is the "click test" this requires a cautious steady hand.
Wih the amp powered up, and at it's full lethal potential, you probe various parts of the circuit to try to trace where your problem is.
Set your meter on DC volts, ground the black probe to the chassis, and probe with the red...touch it to your plate feed resistors in the preamp, basically anything going to pins 1, 2, 7 & 9 on preamp tubes and pins 7 & 9 on poweramp tubes.

Make sure you have the amp powered up with the volume up about half way, plugged into a speaker.
Be prepared for a loudish click sound when you touch the probe to the various points

If you get no clicks at all check your output wiring first.

Report back with yor findings.

Don't let your hand slip.

And be aware that this is somewat dangerous....anytime you're probing a live amp, that is.
You've already taken voltages, so if you had your volume up during that test and didn't hear any clicks there's your first clue.
gotta run...

kd · Post by kd » Mon 07/24/06 11:05 am

touch it to your plate feed resistors in the preamp, basically anything going to pins 1, 2, 7 & 9 on preamp tubes

Clarification- pins 1. 2, 6, & 7. Pin 9 is a heater.

Ken

looper · Post by **looper** » Mon 07/24/06 11:27 am

Sweet I will try it !!........... Nothing no sound still... I checked my wiring again I can't see anything wrong that does not mean alot.Thanks for the reply!

brownnote · Post by **brownnote** » Mon 07/24/06 11:37 am

ooops I meant to say preamp: 1, 2, 6, 7
power amp 7 &9
duh...

looper · Post by **looper** » Mon 07/24/06 2:29 pm

Still no luck I just can't figure it out theirs got to be an answer

Post by **Plexi** » Mon 07/24/06 2:43 pm

If there is no sound at all, make sure you didn't leave off the ground on the feedback switch which i can't see in the pic you posted, measure to see if you have voltage at the tail resistor.... I'd also look at the output wireing on the jacks.

Richie

looper · Post by **looper** » Mon 07/24/06 3:35 pm

I checked the ground I think it should be fine I took a better pic of that section maybe I screwed up the 1/2 power switch? I don't know what is the tail resistor sorry can you explain....Thanks for all the help!!

looper · Post by **looper** » Mon 07/24/06 7:29 pm

It finally works and it sounds grrrrrrrrrrrreat !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!I am so stupid It was a post that I mounted to the chassis for the 2 8k2 res going to pins 2 on the power tubes that I did not even think about the fact it was going directly to the chassis.I hope explained it alright.Thanks to everyone hear at 18 watt for all the help and support.I cannot beleive how good this thing sounds!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Chubsman · Post by **Chubsman** » Thu 07/27/06 8:11 am

I guess your right.... Grounding the inputs (pin2) of the output tubes will not make an amp sound very loud...

Good work!!

rollingelbow · Post by **rollingelbow** » Sat 08/12/06 11:05 pm

Oh man.. I have zero sound in my HO and now that i take a look, the tag board between the resistor and pin 7 on V4 attaches to the chassis. I attached the the resistor and wire coming from the input jack to the center eyelet on the tag board but it runs down to ground.... essentially i am grounding myself right from input. This might be why I am getting zero sound as well right?

Also, is there a tutorial on how to read B + voltages on various parts of the amp? I've got an understanding of the schema and what to read and how to read safely, but I'd like to understand more about strategies and what you can get from this troubleshooting.

thanks.

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36 watt - no sound ... help

36 watt - no sound ... help

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