Coil split - still I got signal from inactive coil

[mobei]

Hey guys,

I did my first coil splitting of a humbucker today, which involved converting a 2-wire pickup to a 4-wire pickup. When I tested my humbucker afterwards by tapping on the coils with a screwdriver I realized that even though the desired coil is louder, there is still a weak signal from the theoretically inactive PU. The wiring I did is the following:

Cable A - North Start - Hot output

Cable B - North End - Connected to C and grounded (coil split)

Cable C - South End - Connected to B and grounded (coil split)

Cable D - South Start and Ground of PU casing - grounded


The very weird thing is: Even when I completely disconnect both coils by cutting B-C, then connect A and D to my audio jack, I get a weak signal involving both coils! That should be impossible, as between A and D there is no direct connection... Is this a normale sideeffect (inductive?) or have I messed up some stuff? The pickup works and and it is clearly audible that the North coil is way louder when I ground B-C, so I think there is no general wiring issue....

Thanks guys!

 

[Clint 55]

Re: Coil split - still I got signal from inactive coil

I've always noticed that also.

 

[Swyse]

Re: Coil split - still I got signal from inactive coil

Are you sure its not noise from vibrating the guitar? Have you tried hitting it with something non-magnetic?

 

[mobei]

Re: Coil split - still I got signal from inactive coil

Yep I'm 100% sure. I can't be the guitar as I did the test outside of the git, just the bucker connected to an audio jack.

So I guess you guys know that you can play music from your phone over a pickup as the speaker movements involve electromagnetics. I tried that the with the wires B and C disconnected from each other and from anything else - still got a small playback over the amp, even though there is NO CONNECTION between the two, thus no coil should be active. Could it be that one coil is inducing the signal to the other one? And is there a way to erase it?

 

[Clint 55]

Re: Coil split - still I got signal from inactive coil

Could it be that one coil is inducing the signal to the other one?

That would be my guess.

 

[AlexR]

Re: Coil split - still I got signal from inactive coil

By tapping you also have physical movement in the connectivity between coils.....so there could be that.
But there could be something in a not perfect ground connection.

Remember tapping is not the same as actually playing through the pickup.

 

[freefrog]

Re: Coil split - still I got signal from inactive coil

Hey guys,

I did my first coil splitting of a humbucker today, which involved converting a 2-wire pickup to a 4-wire pickup. When I tested my humbucker afterwards by tapping on the coils with a screwdriver I realized that even though the desired coil is louder, there is still a weak signal from the theoretically inactive PU. The wiring I did is the following:

Cable A - North Start - Hot output

Cable B - North End - Connected to C and grounded (coil split)

Cable C - South End - Connected to B and grounded (coil split)

Cable D - South Start and Ground of PU casing - grounded


The very weird thing is: Even when I completely disconnect both coils by cutting B-C, then connect A and D to my audio jack, I get a weak signal involving both coils! That should be impossible, as between A and D there is no direct connection... Is this a normale sideeffect (inductive?) or have I messed up some stuff? The pickup works and and it is clearly audible that the North coil is way louder when I ground B-C, so I think there is no general wiring issue....

Thanks guys!

My "morning thought before I get my coffee" is this one: when you tap with the metallic mass of your screwdriver on the magnetic poles of the inert coil, you "excite" the bar magnet. This magnet "excites" the poles in the active coil and it makes sound...

If my thought changes after my coffee, I'll chime in again. )

 

[Clint 55]

Re: Coil split - still I got signal from inactive coil

^^ Nice thinking!

 

[GuitarDoc]

Re: Coil split - still I got signal from inactive coil

MOBEI, what you are describing is perfectly normal...nothing wrong with the wiring or function of the pup. Even though the south coil would seem to be completely grounded-out and eliminated from the electrical circuit, it still has some magnetic affect on the active north coil. Remember that the two coils share the same magnet.

 

[mobei]

Re: Coil split - still I got signal from inactive coil

MOBEI, what you are describing is perfectly normal...nothing wrong with the wiring or function of the pup. Even though the south coil would seem to be completely grounded-out and eliminated from the electrical circuit, it still has some magnetic affect on the active north coil. Remember that the two coils share the same magnet.

Good to know, thank you for your help guys! :knockedou