Strat pickup wiring help...please!

lincolnblue

I'm just getting round to changing the pickups in my old strat copy. This is a cheap guitar I got when I was about 12 but has big sentimental value.

On taking the scratch plate off it seems that the pickup signal wires don't go where the ought (I think?!)


As I understand it from the photo below, the right hand white wire should be bridge, the one to the left of the red should be the middle and the one next to that (hidden behind the green wire) should be neck.



It seems from the awkward wiring that the far left is middle, to the right of that is beck and then far right is bridge. (See below labelled photo)



Which should be right?

Also all ground wires (not just pickups) are soldered in the same place ...does that matter?

Funkfingers

Apart from the volume pot, the photographs appear to illustrate a Chinese-made STRAT.

I am slightly confused by some of the connections to your seven-contact selector switch. Usually, these are three contacts per pole plus a shared output contact that collects the signals from the other six. It would help to be able to see the tracks on the PCB to determine what is supposed to go where.

You appear to have, L-R,
1 - Neck pickup
2 - Middle pickup
3 - Link to 4
4 - Link from 3 + signal output to volume pot (Red)
5 - Upper Tone pot (White)
6 - Lower Tone pot (Green)
7 - Bridge pickup.
8 - Switch chassis ground lug.

If your MNB labelling were correct, position 2 on the selector switch would give Neck + Bridge pickups, in parallel, in phase, not hum-cancelling. Positions 3 and 5 would be reversed. Test for this by amplifying the guitar and tapping on the polepieces to confirm which pickups are connected in each selector switch position.

It is possible to reinstate the stock wiring using the stock parts. It is possible to mildly upgrade the controls via a few minor alterations. The smart option is to renew all of the control parts.

SteveRobinson

You have a non-standard switch. I've seen these before but I can't recall the exact pinout.

Does it switch the pickups as expected? If so it's wired correctly.

All earths together on one pot (plus the links between pots) is correct

lincolnblue

Thanks. I do want to change to switch and pots at some stage.

I'll take more photos tomorrow to show the tracks on the PCB. What I want is to have standard strat 5 position switch wiring. 

Interestingly the tone pots are 500k and the volume 250k. I always assumed all pots should be 250k on a strat?

ICBM

lincolnblue said:

Interestingly the tone pots are 500k and the volume 250k. I always assumed all pots should be 250k on a strat?

Normally, yes. Using 500K tone pots actually makes little difference though, actually less than a 500K volume would. I wouldn’t bother changing them unless the taper is poor.

Funkfingers

lincolnblue said:

What I want is to have standard strat 5 position switch wiring. 

You very nearly have that already.

On conventional schematic diagrams for Stratocaster, there has to be a jumper wire to connect the two sides of the selector switch. On your selector switch, the two common/collector contacts are linked internally to a shared output lug. 

lincolnblue said:

Interestingly, the tone pots are 500k and the volume 250k. I always assumed all pots should be 250k on a strat?

From new, all three pots would have been 500k. This is done partly to save production costs but mostly to compensate for the fact that those "dime" pots are rubbish.

The 250k pot in your guitar is not original. Whoever installed it is probably also responsible for the melted insulation on the green and white wires to the tone pots.

lincolnblue

Funkfingers said:

lincolnblue said:

What I want is to have standard strat 5 position switch wiring. 

You very nearly have that already.

On conventional schematic diagrams for Stratocaster, there has to be a jumper wire to connect the two sides of the selector switch. On your selector switch, the two common/collector contacts are linked internally to a shared output lug. 

So without buying a new selector switch how do I get it to standard wiring?

ICBM

In what way is it not standard now? What pickups do you get in each of the positions?

lincolnblue

Funkfingers said:

lincolnblue said:

What I want is to have standard strat 5 position switch wiring. 

You very nearly have that already.

On conventional schematic diagrams for Stratocaster, there has to be a jumper wire to connect the two sides of the selector switch. On your selector switch, the two common/collector contacts are linked internally to a shared output lug. 

lincolnblue said:

Interestingly, the tone pots are 500k and the volume 250k. I always assumed all pots should be 250k on a strat?

From new, all three pots would have been 500k. This is done partly to save production costs but mostly to compensate for the fact that those "dime" pots are rubbish.

The 250k pot in your guitar is not original. Whoever installed it is probably also responsible for the melted insulation on the green and white wires to the tone pots.

I've had the guitar from new and have never had any wiring done on it so the pots must be factory fitted. It was a very cheap "legend" branded guitar so could just have been badly put together

lincolnblue

ICBM said:

In what way is it not standard now? What pickups do you get in each of the positions?

I think it is standard (will have to check tomorrow when I plug it in) but as @Funkfingers said I "very nearly" had it, I'm just curious to know how it's not quite right. 

I'll check tomorrow was I say but it just seems strange that the middle and neck wiring lugs seemed to be the wrong way round to what it "should" be

lincolnblue

Will I save myself lots of hassle by waiting to change the pickups until I have new pots and a new selector switch?

ICBM

lincolnblue said:

Will I save myself lots of hassle by waiting to change the pickups until I have new pots and a new selector switch?

Yes, probably.

If you want to change them first just duplicate the existing wiring.

lincolnblue

ICBM said:

lincolnblue said:

Will I save myself lots of hassle by waiting to change the pickups until I have new pots and a new selector switch?

Yes, probably.

If you want to change them first just duplicate the existing wiring.

Thanks. Having never done this before, what sort of selector switch and pots should I be looking for and where's good to buy from?

ICBM

lincolnblue said:

Having never done this before, what sort of selector switch and pots should I be looking for and where's good to buy from?

CRL switch, CTS pots. Any of the usual online vendors will do them. It really isn’t worth cutting corners, the cheaper parts aren’t much cheaper really. I would also get a Switchcraft jack while you’re at it.

lincolnblue

ICBM said:

lincolnblue said:

Having never done this before, what sort of selector switch and pots should I be looking for and where's good to buy from?

CRL switch, CTS pots. Any of the usual online vendors will do them. It really isn’t worth cutting corners, the cheaper parts aren’t much cheaper really. I would also get a Switchcraft jack while you’re at it.

On Allparts for example there's lots of different CTS pots. https://www.allparts.uk.com/collections/250k-pots ;

Any advice greatly appreciated as to which is good to go for for both volume and tone. 

Likewise with the CRL switch https://www.allparts.uk.com/collections/switches-electronics/5-position ;

lincolnblue

Oh and would I need a capacitor for the tone pot? No idea what I'd need to look for there

ICBM

250K Log for both volume and tone. You need split shaft, short bushing for a Strat.

You don’t need a new cap, but if you want to replace it then any .047uF/.05uF cap is fine.

Just had a look at the Allparts prices... wow .

lincolnblue

ICBM said:

250K Log for both volume and tone. You need split shaft, short bushing for a Strat.

You don’t need a new cap, but if you want to replace it then any .047uF/.05uF cap is fine.

Just had a look at the Allparts prices... wow .

By that do you mean they're expensive at the moment? 
Where else is worth looking at?

Funkfingers

lincolnblue said:

I've had the guitar from new and have never had any wiring done on it so the pots must be factory fitted. It was a very cheap "legend" branded guitar so could just have been badly put together

IMO, the full sized volume pot and melted insulation on the green and white wires to the tone pots strongly suggest that somebody has been “under the hood” before you took possession of the guitar. Could be the factory, could be the distributor, could be the retailer.

The 250k volume pot in the photographs has a thicker shaft (ooh, er, missus!) than the two 500k tone pots. It is difficult to imagine a factory changing the drill bit to produce one hole of a different diameter.

The soldering on the volume pot is scrappier than the remainder of the job - as if done by a different hand. 

ICBM said:

In what way is it not standard now?

If the terminals are, left to right, N, M, B, common output, N, M, B, the solid wire jumper connector between 3 and 4 is redundant.

This is speculation on my part. Hence, my request to see the PCB tracks.

ICBM said:

What pickups do you get in each of the positions?

A tap test should answer this.

lincolnblue

ICBM said:

250K Log for both volume and tone. You need split shaft, short bushing for a Strat.

You don’t need a new cap, but if you want to replace it then any .047uF/.05uF cap is fine.

Just had a look at the Allparts prices... wow .

Would these parts be ok?
POT - https://www.axesrus.co.uk/CTS-Pot-Split-Shaft-p/cts59.htm
5-way switch - https://www.axesrus.co.uk/Electroswitch-CRL-Lever-Switches-p/crl3-5.htm

Or would I be better going for this> - https://www.axesrus.co.uk/Standard-Wiring-Kit-Suitable-for-Stratocaster-p/swiringkit.htm

lincolnblue

ICBM said:

250K Log for both volume and tone. You need split shaft, short bushing for a Strat.

You don’t need a new cap, but if you want to replace it then any .047uF/.05uF cap is fine.

Just had a look at the Allparts prices... wow .

Would these parts be ok?
POT - https://www.axesrus.co.uk/CTS-Pot-Split-Shaft-p/cts59.htm
5-way switch - https://www.axesrus.co.uk/Electroswitch-CRL-Lever-Switches-p/crl3-5.htm

Or would I be better going for this> - https://www.axesrus.co.uk/Standard-Wiring-Kit-Suitable-for-Stratocaster-p/swiringkit.htm