Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: Philip_dop on March 05, 2021, 06:04:31 AM

Title: Constant Crackling noise
Post by: Philip_dop on March 05, 2021, 06:04:31 AM

I built my crack a while back.

Now it seem like a problem has started, it crackles quite a bit now where it's unusable.

I've check the resistance and found some issues but not sure what is the cause.

When testing resistance,

Pin 7 and 9 show OL, sometimes it shuts off my voltmeter.

and then pin 13 is also OL doesn't change

I've checked all the solder joints they are solid from what I can see.

It was working fine for a while then this just started.

Please advise

Thanks so much

Title: Re: Constant Crackling noise
Post by: Paul Birkeland on March 05, 2021, 06:14:59 AM

Does your Crack have a Speedball?  If so then the  resistances at 7 and 9 won't be 3K (since you pulled out the 3K resistor to install the Speedball).

How are the voltages?

Title: Re: Constant Crackling noise
Post by: Philip_dop on March 05, 2021, 06:28:48 AM

the voltages are 5-10 volts over.

And yes I do have a speedball kit on it.

Thanks for the help Paul.

Title: Re: Constant Crackling noise
Post by: Paul Birkeland on March 05, 2021, 06:29:27 AM

Can you post the voltages for terminals 1-10?

Title: Re: Constant Crackling noise
Post by: Philip_dop on March 05, 2021, 06:41:27 AM

1 76.6
2 180
3 0
4 176.8
5 89
6 3.5mv
7 101
8 .7
9 106
10 0

Title: Re: Constant Crackling noise
Post by: Paul Birkeland on March 05, 2021, 06:44:39 AM

If you tap on either tube or the chassis plate, does it change the crackling?

Title: Re: Constant Crackling noise
Post by: Philip_dop on March 05, 2021, 06:48:36 AM

yes it does, if i tap the volume knob side it either stops or crackles a bit more.

if i hold the plate down it stops

Title: Re: Constant Crackling noise
Post by: Paul Birkeland on March 05, 2021, 06:50:21 AM

That would tend to suggest that you have a solder joint in the amp that isn't 100% functional.  Reheating all the joints will very likely make this issue go away.

Title: Re: Constant Crackling noise
Post by: Philip_dop on March 05, 2021, 06:51:08 AM

Thanks So much Paul, I'll try that and let you know.