DPDT on/on/on vs. on/off/on

[reluctant-builder]

I don't understand how a switch can be momentary. Does it time-out? Does it kick back to off if put into the momentary on position?  :dontknow:

I'm a little frustrated with that no one is willing to divine how the tone-filter toggle on my Swede works. I understand, from a scientific standpoint, the stance: without a schematic, I can't know how it works. I get, too, that the schematic depicts a different wiring scheme from how the switch is actually wired in my guitar.

However, the mock-up I made seems to depict a fairly rudimentary device. Now, because I'm not adept or knowledgeable when it comes to electronics, I lack the requisite base to suss out the switch's precise workings. I know what it does, but I don't know how it does, nor why. But I'd think a better acumen for electronics would allow an inference that is either exactly the reality of how the switch works or very close to it.

 

[line6man]

I don't understand how a switch can be momentary. Does it time-out? Does it kick back to off if put into the momentary on position?  :dontknow:

I'm a little frustrated with that no one is willing to divine how the tone-filter toggle on my Swede works. I understand, from a scientific standpoint, the stance: without a schematic, I can't know how it works. I get, too, that the schematic depicts a different wiring scheme from how the switch is actually wired in my guitar.

However, the mock-up I made seems to depict a fairly rudimentary device. Now, because I'm not adept or knowledgeable when it comes to electronics, I lack the requisite base to suss out the switch's precise workings. I know what it does, but I don't know how it does, nor why. But I'd think a better acumen for electronics would allow an inference that is either exactly the reality of how the switch works or very close to it.

Momentary usually means spring loaded, in one way or another. It will only stay in one position when physical force (In the case of guitar switches, your finger.) against the switch overcomes it's spring force. When you take your finger off of a pushbutton, for example, the spring action will switch it back to the other position.  

As I said earlier, you are going to need an Ohm meter or continuity tester to figure out the switching pattern of your switch. Only then can you identify what it does in the circuit and in what ways it differs from the schematic.

Do you want to IM again? A lot of your questions are easier to answer chatting in real time.

 

[Cagey]

I'm a little frustrated with that no one is willing to divine how the tone-filter toggle on my Swede works. I understand, from a scientific standpoint, the stance: without a schematic, I can't know how it works. I get, too, that the schematic depicts a different wiring scheme from how the switch is actually wired in my guitar.

I think Line6man has the "momentary" business covered.

As for not being able to tell by looking how that switch works, imagine a drawing of a kitchen layout. It would almost certainly contain a sink, stove and fridge, among other things. You could see where they are and how they're hooked up, but as far as being able to figure out how they work? Fuhgeddaboudit. There isn't enough information there. All you know is there's a sink, stove and fridge. It's just a layout/hookup diagram.

 

[stubhead]

This site has a fairly comprehensive discussion of switches:

http://www.1728.org/guitar.htm

And there's a bunch of links there at the bottom to different pages that the author has written about guitar electronics (even battle-hardened veterans may get a kick out of the "Guitar Photos.") ->
http://www.1728.org/super7.htm

A lot of the problem about trying to explain or understand questions in one of visualization, i.e. I personally try to think of electricity as purple water flowing through plumbing - red and blue water mixed. The pickups are the source of red water and blue water, some things cut out only the red water, some things lower the overall volume (leak = ground), some things work by"leaking" a certain amount of one color or another of the water to ground...

I didn't actually understand it well for a long while after I was still able to wire guitars successfully, just by getting the diagram right. In some ways I still don't understand a few things (what one pickup turns into when combining mis-matched pickups - an inductor?) :icon_scratch: But I can still wire the damn thing IF I'm sure my drawing is correct. I don't even want to know how a double-wafer "Superswitch" works, but I can wire one.

A lot of popular modifications are a result of combining some parts of a diagram with some parts of another. "The way a switch works" is a lot easier to understand visually, in fact I usually can't figure out the questions in any other way - we are lucky to have line6man here....

Over the course of a few months, many moons back we accumulated a full-tilt HOWLING GOB of wiring sites here:

http://www.unofficialwarmoth.com/index.php?topic=281.0

If the answer isn't in there, somewhere, whew... :icon_scratch:

 

[line6man]

In some ways I still don't understand a few things (what one pickup turns into when combining mis-matched pickups - an inductor?)

A magnetic guitar pickup is a complex impedance device. It has a signal source (The transduction of string movement to electric current.), which is in series with the inductance of the coil. Because of all that wire on the coil, there is a resistance in series with that. Because the wraps of wire have to be insulated so that the whole thing doesn't became one big conductor, the insulation acts as a dielectric between the wire wraps, which creates a small capacitance parallel to everything. Then, of course, you could consider your losses as the equivalent of a resistance parallel to everything. When you get down to it, a pickup is a low Q factor inductor. (Low ratio of inductive reactance to equivalent series resistance.)

When you put two pickups in parallel, the impedance drops to 1/([1/Z1]+[1/Z2]) (In other words, if Z1=Z2, ZTotal is one-half.), the inductance and resistance drop, following the same formula, and the capacitance increases to the sum of C1 and C2. This usually doesn't affect the output much, though if you have multiple volumes or a blend pot, you might notice the output drop a bit when the pickups are parallel. (Insertion loss.)  What happens when you combine dissimilar impedances, however, is usually that the lower impedance pickup simply "shorts out" the higher impedance pickup, to some degree. Each pickup's individual properties remain the same, it's simply the way you combine them together than changes the way the circuit behaves.

 

[stubhead]

1/([1/Z1]+[1/Z2])?

OK, cool! NOW I can rock! :headbang1:

(close call there...)

 

[line6man]

1/([1/Z1]+[1/Z2])?

OK, cool! NOW I can rock! :headbang1:

(close call there...)

It'll be on the test, so remember it.  :toothy12:

 

[reluctant-builder]

Do you want to IM again? A lot of your questions are easier to answer chatting in real time.

An IM session one of these days would probably be helpful.

I found two listings on eBay for On-Off-On switches, which seem pretty affordable (versus Stew-Mac, in particular) and look to be nearly the exact same switches (as the ones Stew-Mac offers ... and as each other, visually).

SPDT: http://www.ebay.com/itm/300570745321?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

DPDT: http://www.ebay.com/itm/290571830872?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

One lists the type as SPDT ... so that's single pole, double throw ... but I'm not quite sure what it really means? Is it like Dr. Frankenstein's switch, which looks like a tuning fork, where the lever is pushed and the fork's two tines activate the switch? (I gather, too, that Dr. Frank's is a "knife switch.")

The other is DPDT, and I know what that stands for ... but I don't get how it differs from the former because they look identical. They each have six terminals on the bottom and one baton as the toggle.

This diagram only adds to my confusion:

They're both "center on" switches, but they are obviously different. How the heck are you supposed to know which switch has which type of internal connections?

 

[line6man]

The other is DPDT, and I know what that stands for ... but I don't get how it differs from the former because they look identical. They each have six terminals on the bottom and one baton as the toggle.

I'm not sure what you're talking about. The first link shows a three-terminal switch, while the second shows a six-terminal switch.

Regarding Center-on versus SP3T/On-On-On, if the side of the switch is not labelled, you would have to use an Ohm meter to identify the switching. Ask the seller if you are unsure, or order from a switch distributor, using the part number of the switch you want.

 

[reluctant-builder]

Jeez, you know, I didn't even notice the view of the switch from the side. Rather than sheer stupidity, I'll chalk that one up to not having my contact lenses in when I made the post. Squinting at the screen is no way to post to forums, apparently.

 

[reluctant-builder]

OK. I tested the continuity between the terminals of my tone-filter switch and I've attached representations of between which terminals the current travels in which toggle positions. That is, any two terminals connected by an arced red line means I got a beep when touching those two terminals.

First image is with the switch to the right, second with the toggle in its center position, third is with the toggle to the left.