tapped humbuckers

If you're connecting a new pickup, the earth can be connected to any earth. One of the pot casings is usually a favourite, but this is not to be attempted if you don'e have a high power soldering iron. The time it takes to heat up the pot casing with a normal soldering iron means it's hot for too long and the heat spreads, sometimes damaging the pot. There will usually be at least one tag on the volume pot which is connected to earth (sometimes just by bending it to touch its own casing and soldering it). That can be a good place, but again if the tag has been soldered to the case you get the same problem with the heat. Another good place would be the same tag on the output jack that the earth from the bridge is connected.

thanks dave. will connect it to the bridge/jack earth point. n1 bud

well, today i hooked up the yamaha for the first time to see what the new pickup sounds like. its a case of 'mission failed' im afraid. the vol and tone pots hum big time when touched. the bridge and neck pickups dont come on until the coil tap switch for the centre pickup is flicked over. lots o stuff like that etc. i cant see where ive gone so wrong. ive tried to be as precise and thoughtful about what i was doing but its just totally messed up. nightmare.

If your getting hum its probably the bridge point. Where your main ground is, make sure that the wire is touching the metal and its not 'floating' around in the solder. You get some connectivity with solder but its not enough by itself to ground too, so make sure thats okay, same goes with all your other ground points.

I kept getting terrible hum when i first did mine, and couldn't for the life of me figure out what it was, ended up being a bad earth.

Sounds like a bad earth to me, too.

Have you completely re-wired the whole thing, or just added the new pickup and left the rest as it came?

the original 2 h/b's remain. i took out the single coil, in mid position, and put in a s/c sized h/b. its a 5 wire job. the orange and white go to the centre position of the dpdt switch. the green goes to the correct place on the 5 way switch. the bare earth and the black wire go to a junction point between the bridge and the output jack. ive changed nowt really, just the cap between the two pots, thats it.the earth from the dpdt switch goes to the tone pot btw. ive been as careful and thoughtful as i can, but.... Using bthe 5 way sw, the n and b h/b's dont work unless i flick the coil tap switch for the mid pickup. theres a hum on b oth knobs (metal ones) and it seems the c/taps on the n and b h/b's dont do owt. im stumped mate. i cant even begin to guess whats wrong

forgot to say, vol and tone pots are the switched type of pot. sry

Do the original two humbuckers work still, apart from the humming (useful if you're playing a song you don't know the words to!)

lol dave mate. they dont, until the centre pickup tap switch is thrown, then they work. bloody queer gear bud

In that case it sounds like the centre pup tap switch is suddenly earthing everything rather than just earthing one of the coils of the centre pup. Do you have a multimeter with a continuity tester? (i.e. beeps when the probes are shorted?) That would be a good way of finding out what's going on. attach one probe to a known earth and then poke about with the other probe around the rest of the circuit with the centre pup coil tap switch in both positions to see where the unintended earth is happening. It may be you've either got the colour code for the humbucker leads wrong or just inadvertently connected it incorrectly.

well guys, im gonna have to admit defeat with the yamaha. ive tried allsorts and i still cant get it to work. im trying to find the software to do a diagram for you to look at and see what you think. i finally got the centre pickup to work and be tapped, but at the expense of the other two pickups. pos 2, and 4 on the selector operate the centre pickup only without either h/b kicking in. thoroughly stumped now, just dont get it at all