Coil Tap with a SPDT switch?

i have a dimarzio (4 wire) humbucker I'm putting into a Bluesboy clone. I'd like to add a coil tap, but can't seem to find a diagram for this.

Is it possible?

It's just a simple on/off mini switch. in my head it should work to just isolate one pole?

doesn't it?

or do i need a on/off/on switch?

your help is always appreciated. In my head this wiring would go before the 3 switch, and after that it'd be stock?

Here is a pic of the diagram i'm starting with.

Toggle before the main switch. With an SPDT on-off-on you can connect the coils junction to the center. One pole is ground, the other connects it to the p/ups normal Hot lead which is connected normally. Off you get the HB. Up or down either the Screw or Slug coil alone. Or if you want just one single coil sound, use a SPST, that either goes to ground or connects the junction to the Hot lead depending which coil you prefer.Off, the HB. On, the single coil.

any dual coil, 4 wire pup can be "coil tapped" with an spst - one side of the spst solders to ground, the other side solders to where the two leads of the pup are joined (the finish wires of each coil). in essence, one coil is shunted to ground whilst the other stays hot.

in essence, one coil is shunted to ground whilst the other stays hot.

so the rephrase


I just add a connection to ground (back of pot perhaps?), and the 2 wires that are soldered together and taped get soldered to the other lug? Presto?

How can you determine which pole you'd prefer to isolate?

so the rephrase


I just add a connection to ground (back of pot perhaps?), and the 2 wires that are soldered together and taped get soldered to the other lug? Presto?

correct

How can you determine which pole you'd prefer to isolate?

typically, that will kill the screw coil. reverse the pickup ground and hot wires to kill the slug coil. note - this make create a phasing issue with other pups.



....

Or just go to the Hot lead as it enters the switch instead of ground. The screw coil is a little darker on the HBs I've tried, taking into account the place its picking up on the string.

There's a very helpful diagram on the SD site. I even got it right the first time.