Constant Crackling noise

[Philip_dop]

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

 

[Paul Birkeland]

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?

 

[Philip_dop]

the voltages are 5-10 volts over.

And yes I do have a speedball kit on it.

Thanks for the help Paul.

 

[Paul Birkeland]

Can you post the voltages for terminals 1-10?

 

[Philip_dop]

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

 

[Paul Birkeland]

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

 

[Philip_dop]

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

 

[Paul Birkeland]

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.

 

[Philip_dop]

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