Hairball 1176 rev.A - Fine but...

[hugo]

Hi all,
I just finished my 1176rev.A from hairball audio. Everything is working well, but i have still one problem..
On the output pot, there is a point (arround 5o'clock), who makes the unit very noisy directly. ALl is good when i'm not to that point, but when i go over that point on the output pot, the unit starts to clic clic, shhhhhh...and at this precise point, the unit is hesitating between normal,and clicliclic..DOes somebody have an idea. I will maybe change the pot and try with a higher resistance.. Good idea ?

 

[Echo North]

That's oscillation. It's usually caused by wiring being too close to the PCB.  Start with the shielded wires and get them moved around.

Mike

 

[hugo]

Thanks a lot for your fast answer

 

[Di_Sousa]

On the output pot, there is a point (arround 5o'clock), who makes the unit very noisy directly.

What do you mean By 5o'clock?

It's the Output Pot close to zero? close to the full clockwise position?

 

[hugo]

Yes, almost full clockwise. But at a precise point...clicliclic and if icontinue to turn the output pot...shhhhh

 

[Di_Sousa]

Yes, almost full clockwise. But at a precise point...clicliclic and if icontinue to turn the output pot...shhhhh

To be honest never used the output so high. I think I never needed to go past 3 o clock on the output.

 

[Echo North]

Keep in mind your unit may oscillate when the enclosure lid is off, but may be fine with the lid on and in the rack as the enclosure provides shielding.

Also, you can try shielding the wires that go from the meter PCB to the output XLR. Just disconnect the shield on the meter PCB side and connect the shield to pin 1 on the XLR side.

Mike

 

[hugo]

Yes, almost full clockwise. But at a precise point...clicliclic and if icontinue to turn the output pot...shhhhh

To be honest never used the output so high. I think I never needed to go past 3 o clock on the output.

I agree, but it is frustrating to have any trouble when diy...and i think if i solve this problem, maybe the unit would be less noisy, even  at other levels.

 

[Di_Sousa]

Yes, definitely.

Now it's time to troubleshoot and fix it
wish all good