MIJ Squier

[greybagz]

Hi Everyone,
Hope you all had a great Xmas and New Year. I've got another guitar that requires some attention in the wiring department. It's a MIJ Squier with 2 Seymour Duncan (cheapies?) 1x Single coil and 1x Humbucker. I have sketched a diagram of what's inside and would like some advice on whether it's correct or not, as I am not familiar with the current wiring it has(Its quite messy and I'd like to clean it up). Now i don't know much about active pickups so I recorded these readings so you have a better idea of whats happening. Each pickup has a Red, White, and Bare wire and these are the readings i obtained approx.
Neck
*Red - White = 170k
*Red - Bare = 47k
*White - Bare = 160k
Bridge
*Red - White = 190k
*Red - Bare = 47k
*White - Bare = 190k
The strange thing i found was that it has 2x 9volt batteries in series, another thing I've never seen. So I'm really stumped with this. Is it normal? Any suggestions to make her work with the current switch and pot arrangement?
I'm unsure of pot values.
The 502k 100v resistor looks like a green cap but is yellow, and the 0.1M 50v cap is orange ceramic type. Hopefully enough info.

[JohnH]

Hi greybagz

Totally weird, but I am also not familiar with those pickups.

Could you add some descriptions of how it all works in practice, particuarly the switches in their various positions?. Also, I'd have expected the left and centre volume pot lugs to be the other way round. Does it work well?

cheers

John

[greybagz]

John,
It does not work well at all, I've only just acquired this guitar. Mainly for a bit of experimentation and an intro to active pickups. The pots will need either a good spray with contact cleaner or will need to be replaced (very scratchy). I'm not sure who wired it like this, I managed to get one sound out of it, (sorry but I can't remember which PU it was). I will put the batteries back in and report my findings for you all this afternoon. I know that it was only working in one position.
Talk soon.
Graeme

[JohnH]

This seems to be the intended way to wire these pups:

www.seymourduncan.com/support/wiring-diagrams/schematics.php?schematic=livewire_1v_1t_3way

Its showing a standard LP-style toggle, but it could be adapted to two simple two-position toggles for on/off on each pup, with a kill-switch setting when both are off.

John

[ChrisK]

Since these are active pickups, resistance measurements are meaningless. You're not measuring the coils, but the leakage currents in the OPAMP output stages.

The two 9VDC batteries in series just increase the supply voltage and therefore increase the signal headroom.

The "bare screen" leads are not screens only, but are also the battery power supply return. Make sure that they are really wire/solder hard connected to ground (and not just thru the pickguard foil).

Your diagram should work, maybe some things are toast(ed).

And, as JohnH sez, the volume pot has its hot and wiper connections reversed.

[greybagz]

Excellent, thank you guys for the help. I will set out to repair it tonight. Chris, Just looking closely at the connections I've noticed one of the bare wires only hanging by a thread on a dodgy solder joint, so you've most likely nailed the p/u that wasn't working on the head, thanks for the insight regarding active pickups.
JohnH, thanks for the diagram link it explains alot regarding pot, cap values etc.
Any ideas on the 502k 100v component and the high value ceramic cap (.1M 50v) being used?
Would you suggest following Seymour Duncan diagram for best result.
Back Soon
Graeme

[JohnH]

My take on it is that because the pups are active, everything happens at lower impedance. Hence pots are lower, ie 100k instead of 500k (what pots do you have?) The tone cap seems like it is 0.1M meaning 0.1 of a million picofarads = 0.1µF. This, with a low impedance system featuring 100k pots would be similar in tonal action to a more usual 0.022µF with 500k pots.

The other doovelakee, noted as 502k 100V strikes me a being another cap. Not sure how to read the value. In that circuit, with the on/off/on switch, you would have bridge off in centre, bridge fully on one way, or just high treble form the bridge when switched the other way.

That makes a bit of sense I think - I hope it works!

John

ps - Sumgai recently taught me to write µ symbols - see, I can do it now!

[greybagz]

Hello again,
Completed repair to guitar. swapped connections at vol pot wiper, resoldered bare wires from pickups and cleaned pots inards. Guitar works fine and sounds great.
JohnH, switches work as you said
Neck on/ off.
Bridge on/ off/ on with high treble (not a great sound, but different).
As always, everyones help is much appreciated, thanks again for all the knowledge.
Graeme
"Doovelakee" ha ha, I haven't said that in ages.

P.S. Can we all learn how to type the 'micro' symbol?

[sumgai]

Graeme,

Ye, sure can! Just type in the following characters: µ - that's it!



sumgai