Foreplay Hum Left Channel Only

[JFugazzi]

Hello

Finished my Foreplay tonight and it has a loud hum on the left channel but only on the first two steps
of the volume control. Once I get to the third setting the hum goes away and I can listen normally.
I'm assuming its a problem with the volume control but everything seems to be connected ok there. Anyone
ever have this problem and how did you fix it?

Thanks

Joe Fugazzi

 

[Grainger49]

If it hums on all inputs on the first two steps it might be the solder joints on the first two steps of your left SW.  I think that will only be 4 solder joints to rewet.

If it is only one input then check the ground for that input, resolder it.  Do the same for the wire coming from the hot of that input to the terminal strip and the 33k ohm resistor's soldering to the selector switch.  But this is less likely with the "first two steps" symptom.

Luckily you have a very simple circuit and only a few things to check here. 

 

[JFugazzi]

Success!!....Resoldered all points on the sweet whispers and the input switch and the hum is gone.

 

[Grainger49]

So, now, how does it sound in your system?

Glad you got it fixed.  Doc and PJ put a lot of refinements into the FP III over the tiny FP 2.  Many of those were to eliminate hum.  And they are successful most of the time.

Your precise description of your problem pointed right at the area where you could fix it.

Congratulations!

 

[FastEddy]

JFugazzi: " Success!!....Resoldered all points on the sweet whispers and the input switch and the hum is gone. ..."

Seems that this is probably my problem(s) as well = slight hum in both channels. Seems I'll have to breakout the ol' soldering iron too. Thanks ...