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Pro-ject debut carbon USB - Humming problem

L

law852

New Member
Need help diagnosing and fixing my pro-ject debut carbon USB, which has a built-in pre-amp.

I've owned it for ten years, never a problem until just recently, it's suddenly sending a loud hum to the amp. It's not a hum from the motor, it's something digital. It hums even when turned off. Unplugging power supply does stop the hum.

It's not my amp. It's definitely the TT. Maybe a cold joint or bad capacitor?? But I don't know enough to 1) identify the problem and 2) fix it.

Any help/guidance would be very appreciated!!!!
 
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Try pulling & reinserting the interconnects, several times, between the turntable and the receiver.

Could be some corrosion developed on the contacts.

Is the ground wire from the turntable secure?
 
Mr Boochie said:
Try pulling & reinserting the interconnects, several times, between the turntable and the receiver.

Could be some corrosion developed on the contacts.

Is the ground wire from the turntable secure?
Click to expand...
Yes, I've tried multiple RCA cables just to make sure it's not a problem with the cables - and also visually examined the contacts, which look OK. And yes, ground wire is secure.
 
law852 said:
Yes, I've tried multiple RCA cables just to make sure it's not a problem with the cables - and also visually examined the contacts, which look OK. And yes, ground wire is secure.
Click to expand...
Darn, too bad it isn't an external problem.

Now it sounds like an internal wiring problem within the turntable.

The headshell is not removable. Right?
 
Mr Boochie said:
Darn, too bad it isn't an external problem.

Now it sounds like an internal wiring problem within the turntable.

The headshell is not removable. Right?
Click to expand...
Correct, headshell is not removable....I'm thinking I need to just take a magnifying glass and inspect all the solder joints, if there's a cold joint then I have my answer, and I can try to resolder it... if no cold solder joints, then back to square one!!!
unless there's something else simpler I hsould try first?
 
law852 said:
Correct, headshell is not removable....I'm thinking I need to just take a magnifying glass and inspect all the solder joints, if there's a cold joint then I have my answer, and I can try to resolder it... if no cold solder joints, then back to square one!!!
unless there's something else simpler I hsould try first?
Click to expand...
Take out the magnifying glass.

Sorry. :(
 
Hi law852 - I am having the exact same problem! I've already pulled out the circuit board and have been probing for any burnt components. Could you post a photo of which cap went bad? It might make my search easier.
 
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