Author Topic: Advice on bad wiring (Read 5170 times)

Elliot · « **on:** February 14, 2006, 10:42:22 AM »

I started playing my strat today and heard an foul crackle on chords - after playing with the jack plug (which had come loose) I touched the volume control pickup screw on the neck pickup (I had the neck on) and this made a live microphonic hum sound.

Do I just need to resolder the neck pup into place again or is a sign of something worse?

PhilKing · « **Reply #1 on:** February 14, 2006, 12:15:29 PM »

Do you mean the height adjuster screw? Is it the same sound as when you touch the tip of the jack? Does the same happen if you touch the bridge? If you have a full grounding shiled plate under the pick guard, then it sounds like you have live in the shield.

The first thing I would check is that the jack socket is OK. Also try a different lead. If the socket is OK and you get the same sound with a different lead, you need to check the wiring on the guitar.

Elliot · « **Reply #2 on:** February 15, 2006, 09:06:09 AM »

Phil - that's exactly where the problem is and what it sounds like. The cable is fine - I have tried a different one and it does the same.

The jack plug is loose, its as tight as I can screw it with my fingers - I don't have the tool to screw it in tight - could this cause the problem?

Elliot · « **Reply #3 on:** February 15, 2006, 11:54:19 AM »

OK its not the jack plug connection - i've just tightened it and resoldered the connections.

Strange thing is - I just put new pickup adjustment screws in and before the crackle and live sound would be on the middle - now that has gone but it has moved to the neck.

Any thoughts - as I have just re-stringed the guitar i'll wait a month until my next string change but is it more likely to be at the pot (which has had a good number of pickups soldered to it over the years and so it probably a bit of a mess) or the switch?

PhilKing · « **Reply #4 on:** February 15, 2006, 12:14:21 PM »

Do you have the full shielding plate on the back of the pick guard? It could be the screws making contact with that. Do you use springs or the plastic tube between the pickups and the pickguard? If it is an earthing problem, it might be that the neck screws are not making contact now but the middle ones are. In terms of the switch or the pots, you could take of the switch tip and see if you get the sound then.

It's really hard to tell without seeing it. I would just unsolder everything and redo it! Make sure the earth wire to the bridge is connected to ground too.

Elliot · « **Reply #5 on:** February 15, 2006, 12:25:28 PM »

Cheers phil - i'll investigate when March's strings go on :D

sambo · « **Reply #6 on:** February 15, 2006, 12:29:15 PM »

haha investigate- look at your avatar hahaa!

Elliot · « **Reply #7 on:** February 15, 2006, 08:39:09 PM »

I fixed it - it was elementary - I took the offending pickup adjustor screw out and noticed it had slipped out of it rubber sleeve inside the scratch plate. So it was conducting like Simon Rattle.

Cheers Phil.