So many wires!!!

[Batbastard]

Hi guys.
I recently bought a ‘96 Fender Cowpoke with the Stu Hamm/Phillip Kubicki active pre amp.

Let start this by saying: I know NOTHING about wiring or electronics but here I am starting to learn.

The bass has a lot (I mean A LOT) of hum.

I’m pretty sure it’s not just 60 cycle hum as a Jazz bass plugged in with the same cable, amp and everything in the same room is silent.

It doesn’t stop when I touch the strings either.

My reading leads me to suspect a Ground issu so I jumped on YouTube to learn about that before checking the most likely candidate: The jack socket.

Again YouTube told me to expect two wires, one hot, one ground on two lugs but when I opened it up there are FIVE wires soldered to the (very rusty) jack.

Can anyone please tell me a) What the hell all these wires are and
b) how to proceed?

TIA.

 

[Matt Liebenau]

The red wire should be the signal or hot from the preamp. The connection with the 3 wires should be ground. Not sure what the 3 wires are without tracing them out. Maybe signal ground, bridge ground and ??? The single black wire should be the battery negative which turns the preamp on when you plug in a cord. As far as what to try next, none of those solder connections look awful. You should check the connections inside the control cavity. Maybe clean the contacts inside the jack. They look a little corroded or dirty.

 

[Batbastard]

The red wire should be the signal or hot from the preamp. The connection with the 3 wires should be ground. Not sure what the 3 wires are without tracing them out. Maybe signal ground, bridge ground and ??? The single black wire should be the battery negative which turns the preamp on when you plug in a cord. As far as what to try next, none of those solder connections look awful. You should check the connections inside the control cavity. Maybe clean the contacts inside the jack. They look a little corroded or dirty.

Thank you. Is it worth just resoldering then all to make sure?

 

[Killed_by_Death]

before you break out the soldering iron, break out the multimeter & start checking connectivity

 

[Matt Liebenau]

It shouldn’t hurt. You could also try plugging into the jack while it is out of the bass. The signal contact could be hitting shielding or some other ground point inside the cavity when there is a plug in it.

 

[Batbastard]

It shouldn’t hurt. You could also try plugging into the jack while it is out of the bass. The signal contact could be hitting shielding or some other ground point inside the cavity when there is a plug in it.

Cool. Thank you.

 

[Batbastard]

I found the fault.
It’s the main connection between the wiring and the PC board.
I’ve got a guy trying to source a new one and if that fails we will just hard solder the connections to the board.

if anyone is interested I’ve managed to source the service manual from Fender

Two versions:


[This invalid link has been removed]




[This invalid link has been removed]

 

[David Jayne]

Cool bass. Kinda rare.

 

[Artie2]

When you say the "main" connection, are you talking about a connector? One that unplugs? If so, a shot of Caig Labs Deoxit could work wonders, and you'll always use it for pots & switches too. For connectors, I prefer a few drops of this on a Q-tip, rather than spraying the can all over the place.

DeoxIT®, #D100L-2C (Squeeze Tube) - CAIG

 

[Batbastard]

Yup. Exactly that and that’s exactly what we are going to try first before we pick up wire cutters and solder.

but it feels like it might need more than that.