SG Gibson

Trying to get my old SG kit back in action. All pots are working. Switch working in two positions (neck p/up and both p/ups) but not working for bridge p/up. Have re-soldered several 'suspect' joints and the wiring layout is correct for an SG (ie switch going to centre of pot lugs). It's possible I suppose that the bridge p/up is faulty but not sure how to test this. Bought a multi-meter but having trouble understanding how it works (on resistance). Any ideas?Attachment 42993Attachment 42994Attachment 42995Attachment 42996Attachment 42997

In the 'both pickups on' position, is the sound changing, or does it stay the same i.e you still only get the neck pickup? If you are unsure, tap each pickup in turn lightly with a screwdriver and you should hear a 'thunk' through the amp for each one.

The grounded screen of the yellow pickup input wire on the second photo looks like it would be very easy for it to touch the input lug on the volume pot and stop the signal.

You generally need to practice your soldering and think about how you connect the wires. If you don't use heat shrink to insulate the exposed screen wires to stop them possibly shorting out a signal wire when installed in the guitar, then adjust the length so that the screen wires are soldered directly to the back of the pots etc. with no excess free length, and have longer signal wires if necessary going to the pot and switch lugs.

Cut off any loose strands of wire left after soldering and try and keep wire lengths to a minimum.

You don't want any chance of the signal being grounded once you put all the wires in the cavity and put the back on.

It also looks like either your soldering iron isn't powerful enough to solder the wires to the back of the pots, or you aren't letting the pot heat up enough before applying the solder. It's forming blobs which are only really tacked on in a few places, rather then the whole mass of solder having melted properly and fully adhering to the pot. Lead-free solder isn't particularly easy to solder to large items like pots as it needs a high temperature to melt and the pot mass sucks away the heat, so you need something powerful to heat up the join before the heat has time to dissipate.

It's best to first clean the back of the pot to get rid of any oxidation, so rub with some P240 or P400 grit paper. Then always tin the back of the pot and the wires to be attached first. It then makes soldering them a lot easier.

As for the multimeter, select the ohms selection, which I think is the straight up/12 o'clock position on your model. It is an auto-ranging meter so you should see a value with the selected range displayed.

Most pickups will have a DC resistance (often shortened to DCR) of between 6k ohms for single coils to 20k (or a bit above) for very powerful humbuckers.

The kit humbuckers normally measure in the 12k-14k ohm region, so I believe you should get a indication that the range selected is 0-20k when you measure the pickup (assuming it's OK). You can stick a lead in the jack socket and on the other end measure between the tip and the sleeve connections with the volume control full up and the relevant pickup selected. You should see a figure appear (say 12.1). If you see all zeros, or an indication of less than 1 ohm, then you've got a short circuit. If you see an overrange or overload indication, then you've got an open circuit.

To test just the pickup itself, rather then the pickup plus the wiring, you need to unsolder the signal wire or the ground wire (or both) and then measure across the pickup lead connection.

Thanks once again Simon. Checked the bridge pickup and no 'clunk'. When I put the multi-meter (mm) across the bridge p/up leads I got an ohm reading of 1346 (whatever that means)! The mm gave readings of approx 7K for both the neck and both p/ups together (they are 'minis' from my LP hollow body from a Chinese kit), whilst the bridge p/up scored a 160K across the jack lugs (presumably therefore an 'open circuit'). I put all the wiring/pots/switch back into my LP hollow and it works properly. So the SG's bridge pickup is the root cause of all my problems. The SG is actually a GuitarAust kit from 2013 and has Wilkinson pickups, which I thought were much better than the PitBull examples; so it's a question of how come the bridge pickup is 'dead' after such a short time. Will take a look at what the supply situation is with electronics and have a go at buying new.

Sounds like a very high resistance solder joint somewhere within the pickup itself. You could try taking it apart and having a look, but a new pickup is probably the answer.

Several people on here have used the Warman Firenbucker II minis with good results. But they only seem to come in pairs. But then again, they aren't expensive.