ES-3 second build custom.

[McCreed]

That's the one I was referring to, and how I would do it if it was my job.

Btw should there be continuity from the red wire to the back of the pickup (I don’t get any) like I get from the bare wire to the back of the pickup?

No. The red wire is your signal (hot/positive etc) and the back plate (or even the cover) of the pickup is going to be connected to ground (negative). That's why you get continuity at the green or bare wires. They are connected to the ground of the pickup.

Here's a screenshot of the wire colour code:


It may help you visualise how HB pickup wiring works.
Note: the bare wire is not shown in the diagram.

[Simon Barden]

No, the red wire doesn’t connect to the back of the pickup. If it did, it would be grounded and you’d get no output as both ends of the pickup connections, green and red, would be connected to ground. I thought I’d answered this in a previous post, but I obviously hadn’t got round to it before posting the reply.

[king casey]

No, the red wire doesn’t connect to the back of the pickup.

Huh? Surely you meant to type 'pot'?

cheers, Mark.

[Simon Barden]

No, Mark was talking about the back of the pickup as the green wire was showing continuity to it.

[DarkMark]

Ok, thanks folks. I think I’ve learnt something today, but I still can’t visualise where all those mysterious wires come from within the pickup. I take it some join from the start and end of the coil. Black and white joining the coils perhaps? Anyhow, let’s see how I go later in the week.

[Simon Barden]

You've got two individual coils in a humbucker. One coil (north) has a black wire and a red wire connected at the two ends of the winding. The other coil (south) has a green wire and a white wire connected at the two ends of its winding.

The separate green, red, black and white wires form part of a 4-core multicore cable, with a braided overall screen on the outside of those 4 wires, which then has an overall insulation covering over it all. The screen is connected at the pickup end just to the brass baseplate of the pickup (which if its covered, is also connected to the cover through a blob of solder at each side of the baseplate). When you buy the pickup, there is no direct connection from the screen to either of the coils or their connections. That comes when you solder it in place to the back of the volume pot.

To make the humbucker work, the two coils need to be connected in series. So you have a ground wire (green) which is the 'start' (all names are nominal) of the south coil. The 'finish' of the south coil (white) is then connected to the 'finish' of the north coil (black), which links the two coils in series. The 'start' of the north coil becomes the signal output of the pickup, which connects to the input lug on the volume control.

The screen needs to be connected to ground in order to reduce hum being picked up from the pickup leads, and also to ground the backplate of the pickup (and the top cover if fitted) for more hum rejection.

You may be wondering why the 'finish' of the south coil is connected to the 'finish' of the north coil, rather than the 'start'. This is because to make two coils humbucking, one coil needs to RWRP (reverse wound, reverse polarity) with respect to the other. So one coil has its steel pole-pieces connected to the 'north' side of the bar magnet (which sits underneath and in-between the two coils, sandwiched between the coils and the base plate) and the other coil has its steel pole-pieces connected to the 'south' side of the bar magnet. So that makes one coil have 'reverse polarity' with respect to the other. To get them 'reverse wound' you don't have to physically wind the coil the other way (though I know some people do, but topographically its just the same), you just connect the wires up the other way around. Which is why you connect the 'finish' of one to the 'finish' of the other. If you connected the 'finish' of one to the 'start' of the other, then the coils would produce a signal of opposite polarity to each other, and you'd get a very thin sound indeed.

So for a humbucking humbucker, you need opposite magnetic polarity for the pole pieces, and the signal to flow the opposite way through one coil compared to the other. So you can connect the two coil 'starts' together, or the two coil 'ends' together'. it really is quite nominal as to how you do it (and different pickup manufacturers do wire up different ways round to other manufacturers, which can result in opposite polarity output signals if they get mixed together).

The result of opposite signal flow path and reverse magnetic coil polarity in one coil (compared to the other) results in the signal from the string producing the same polarity output in both coils, so these add together, but any electrical noise picked up by both coils (which isn't affected by the magnetic polarity at all but is by the relative opposite signal paths) is of opposite polarity in each coil, so the noise cancels out to a very great extent (the physical separation of the two coils means that the noise reaching the two coils will vary slightly in phase so it's never 100% cancellation and often there's a slight mismatch in the number of winds on each coil, so one signal will be slightly stronger than the other; so again, not 100% cancellation).

[DarkMark]

Great layman’s explanation, Simon. Thanks for taking the time to educate me on whats happening under that pickup cover. Much appreciated.

[DarkMark]

So given the above explanation, does that mean I should be able to test for continuity between the;
Green and Black/white wires.
Red and black/white wires.
Green and red wires?
My multi meter is not giving me any.

[king casey]

So given the above explanation, does that mean I should be able to test for continuity between the;
Green and Black/white wires.
Red and black/white wires.
Green and red wires?
My multi meter is not giving me any.

Father's day is coming up, how about a new multi-meter?

cheers, Mark.

[DarkMark]

Father's day is coming up, how about a new multi-meter?

cheers, Mark.

It is new!