This is driving me crazy

brycycle · Post by **brycycle** » Wed Jan 24, 2007 3:10 pm

i go the p/u for my '75 4001 back from Sergio, who diagnosed it as not needing a re-wind, but that the red wire was disconnected and it was reading strong (thanks again Segio).

dropped it in and the treble pup is functioning, but almost inaudible. i replaced all the caps, checked all the wiring/grounds (except the jacks, but about to).

there is a fair bit of ground buzz, remedied when i make contact with a metal piece.

any ideas?

rickfan60 · Post by **rickfan60** » Wed Jan 24, 2007 3:15 pm

The jacks can cause big trouble if they are bent or dirty or both.

rickenbrother · Post by **rickenbrother** » Wed Jan 24, 2007 3:30 pm

Did you put the ground wire from the bridge pickup in place on one of the the height adjustment screws between the spring and the surround plate?

brycycle · Post by **brycycle** » Wed Jan 24, 2007 3:37 pm

Ted - cleaning up the jacks now.

Joey - yes i did.

will let you know what happens when i finish with the jacks.

thanks for the advice

brycycle · Post by **brycycle** » Wed Jan 24, 2007 4:01 pm

huh - still the same problem.

rickboy88 · Post by **rickboy88** » Wed Jan 24, 2007 5:30 pm

Bryce, one of the guys on the forum had a cold solder joint (new Ric bass) causing a ground buzz. Could this be the cause?

brycycle · Post by **brycycle** » Wed Jan 24, 2007 5:47 pm

i've re-soldered every joint and i know the pups are both functioning as they are supposed to.

can a pot every be 'bad'? or should i consider replacing the wires?

i'll re-solder again incase i missed something...

any other advice or suggestions would be appreciated.

rickboy88 · Post by **rickboy88** » Wed Jan 24, 2007 5:56 pm

Bryce, email David Calderon (Jocal62). I believe he's the person who found the cold solder joint. That doesn't appear to be the issue, but he would have a list of things to try from people attempting to help him. Couldn't hurt.

relayer4u · Post by **relayer4u** » Wed Jan 24, 2007 6:11 pm

Pots can fail, no doubt about it.

rickenbrother · Post by **rickenbrother** » Wed Jan 24, 2007 6:24 pm

Have you checked the ground wire that should be soldered to the bottom of the mute bar in the tailpiece?

brycycle · Post by **brycycle** » Wed Jan 24, 2007 7:30 pm

Joey - just re-soldered the entire bass. still minimal output.

i guess i'm left with the options of replacing the wires, or replacing the pots? does that sound about right?

how can i tell if a pot is to blame?

B

jps · Post by **jps** » Thu Jan 25, 2007 2:44 pm

Did you try hot wiring the pickup straight to the output jack as a test?

charlyg · Post by **charlyg** » Thu Jan 25, 2007 4:19 pm

I hot wired mine, but then I ended up in San Diego!

brycycle · Post by **brycycle** » Thu Jan 25, 2007 4:29 pm

no i didn't Jeffrey, i'll give that a shot.

is there a way of determining whether a pot is 'bad'?

charlyg · Post by **charlyg** » Thu Jan 25, 2007 5:03 pm

I have dealt with electronics most of my life. Pots usually do not go completely bad., Normally, they get scratchy, non linear, and noisy. Once in a while they go completely dead. Just set your ohm meter to the range of the post. hook one probe to the middle, and then to one end, turn "knob" and watch meter go up and down. Now hook to other end and repeat. If you want to know the maximum resistance of the pot, read from end to end. The "knob" setting will not change this reading.