pup selector switch setup?

im no electronic genius by any means, but i have wired and (re) installed many acoustic and electric pups, switches, caps and jacks over the years. all of these have been done, for the most part, from actual wiring diagrams.

lately, ive come across a need to really understand what the actual wiring set up of pup selector switches as far as what/where the actual poles on the switches represent, coming and goaing, in the basic 3 and 5 selector switches. hopefully i can extrapolate the setups of the more complicated switches (super) from this basic stuff.

i cant say that ive ever seen an actual diagram as to what goes where to where on these switches. obviously, i can get a very basic idea from the diagrams that ive used, but, what confuses me are the "cross" wires going between the poles themselves, and what that is effecting in the overall wiring schemes.

anyone here know where a diagram like that exists of the switches themselves? i havent found any on my travels across the net on wiring sites.

thanks!

rand z tropicalsoul.net

I'll take a whack at it...

The lever-style pup selectors as used by Fender (and others) are actually two-pole switches. If you look at the STOCK switch, it has two rows of lugs - each row is considered a pole. So, when you work the lever, you are actually throwing TWO switches at once.

Look at the first two switches in this drawing (for now, ignore the second two switches):

http://www.deaf-eddie.net/drawings/5-ways.jpg

I've labeled the lugs to reference which position would be selected (Bridge, Middle, Neck) OR to show that they are the Common lug - that's the unchanging lug that the other lugs are switched between.

As you work the lever, you are moving a wiper which comes in contact with (or loses contact with) the three switchable lugs. The common lug is ALWAYS in contact with the wiper.

A tele scheme is pretty straight ahead - three throws on the switch, three different tones. This is achieved by using one pole (one side) of the switch to select the bridge pup, and the other side of the switch to select the neck pickup. There are actually two ways to do this - you can have the pups connected to the commons, or the output connected to the commons...

In this drawing, the pickups are wired to the commons, and the switchable lugs are jumpered together and on to the output:

http://deaf-eddie.net/tdpri-drawings/tele.jpg

You can see that the neck pup is connected to the output in two throws, the bridge pup is connected in two throws.

NEXT:

Here's a Strat, where they use one pole (one side) to select the pickups, and one pole to select the tone pots:

http://deaf-eddie.net/tdpri-drawings/strat.jpg

On a Strat, the COMMONS are connected and routed to the volume pot. Because the commons are jumpered together, when the neck pup is selected, the neck tone pot is also in the circuit. Same for the middle pup.

Remember, when this switch was first used, Strats also only had THREE throws, and Leo used the same switch in Strats and Teles.

SOME HISTORY:

The #2 and #4 throws (where the Strat's "quack" is) came about because players discovered that because of the way that original 3-way selector was designed ("make before break" style), if you carefully got the lever to stick in the "in-between" spot (between the original #1 and #2, or #2 and #3), the switch's wiper would actually make contact with the next lug BEFORE it lost contact with the previous lug - so you heard TWO pickups on your Strat at once! It was a happy accident, but it was flat amazing!

After a third-party began marketing these 3-way switches with two extra "stops" at throws #2 and #4 (as I recall, late sixties, early seventies), Fender finally made the 5-way selector switch stock on Strats (mid-seventies, if memory serves). The wiring didn't change, just the switch, and only slightly - two new "notches" were made in the mechanical action of the switch, so that it would consistently stop while contacting two of the lugs - so we could all get the magic "in-between" tones.

******

The other two switches in the first drawing are examples of other 5-ways. They still have two poles, but the poles are in-line and one after the other. Can you see them?

There, that seems like a good start. Anybody else want to chime in?

hey, deaf eddie!

that was pretty great of you to explain all of that with the diagrams and all!!!

i cant say that i totally understand it now, but i understand it better than i did before. ill take some time and examine the examples more closely and try to grasp a bit more...

thanks very much for sharing your knowledge!! i hope few others have a chance to see this and understand their switches a little better.

rand z tropicalsoul.net

Here's a drawing I just did that might enlighten a bit more - a side view of a 3-way/5-way:

http://deaf-eddie.net/tdpri-drawings/3-way-side.jpg

This is ONE POLE, remember - it's repeated in mirror-image on the other side of the switch.

You can see that the common lug is always in contact with the wiper, and the contact point on the wiper moves across the switchable lugs as you work the lever.

The magic of the 5-way is that, because the switch was designed as a "make before break", the contact point on the wiper is wide enough to contact the next lug before losing contact with the previous lug - so it CAN "touch" two lugs at once (I'm sure Leo selected this particular switch to eliminate possible "popping" sounds when switching between pickups).

Some Strat player figured that little trick out, fiddled with the switch until he got it to play two pups at once, finding the QUACK - and the rest is history.

All they had to do was to add two mechanical "stops" to the 3-way switch, so that it would stay at the "touching-two-lugs" point in its travel. There's no difference in the lug layout of the standard 3-way and 5-way, it's just a matter of how we wire them up.

thanks again de!

one final question concerning wiring stretching "between" the various poles. does the wiring connecting two poles, from either side, making them a "multiple connection" to connect to whatever configuration, or what?

im still unclear about the "cross wires" running over top the switch (bottom actually), and between various poles.

what is this about?

this is really great and thanks for your knowledge!

rand z tropicalsoul.net

im still unclear about the "cross wires" running over top the switch (bottom actually), and between various poles.

You have to fully grasp the concept that your 3-way (or 5-way) is really TWO separate-but-parallel-and-synchronized switches.

In Strats and Teles, the jumper between the two poles (wires that cross over) are simply to connect the results of those TWO separate switches. It is then sent on to the volume pot.

In the case of the stock Strat, with the two COMMONS jumpered together, it's because one pole runs the pickup selection, and the other pole runs the tone control selection. Now, they could have just connected both commons seperately to the volume pot - yes, they could have run two wires meeting at the volume pot, using NO JUMPERS - and achieved the same thing.

Jumpering them together across the switch is just a "shortcut" to have both the tone-pots-side of the switch and the pickups-side of the switch connected to the volume pot with the minimum amount of wire.

They don't really HAVE to have any lugs jumpered together, there's no circuitry magic - it's just a wiring shortcut.

On a Tele, they used BOTH poles for pickup selection - one pole runs the bridge pup, and one pole runs the neck pup. Adjacent switchable poles are jumpered together because each of the two Tele pups is "on" in two of the three throws - so you gotta have two lugs out of three connected for each pup.

The wire that runs across the switch is, again, a wiring shortcut. They could have run a seperate wire from the bridge side of the switch to the volume pot, and run another wire from the neck side of the switch to the volume pot - but, hey, since we're all going to the same place, why not "hook up and share the ride?"

It's not magic, it's not mysterious electronic wizardry, it's just logicial wiring shortcuts. Leo was nothing if not thrifty and efficent!

deaf eddie,

gotcha!

and thanks again... you've clearly solved the mystery!

rand z tropicalsoul.net