The DPDT or SP3T On-On-On switch. Interesting.

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emrr

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Apr 12, 2006
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I just discovered this beast in an old piece, and figured very few others have encountered it either.  

How to describe?  I can't find a drawing in anyone's catalog.

The two outside throw positions connect to the center pins as normal in an on-on type.   The center position has each center pin connected to one throw position, but opposing position from the other.  Like separating the toggle into two distinct switches in opposite position from one another.

It's used to make a three position toggle switch have fast/medium/slow or low/medium/high settings, as opposed to fast/slow/medium or low/high/medium settings you get trying to use the more common on-off-on type.
 
wow, that´s exactly what I needed for an eq project. I hope I could buy it locally. For now I will have to stick with narrow-wider-normal for Q...
 
I like those switches. Put one on a Seymour Duncan Custom humbucker 20 years ago?! (Crap I'm gettin old :shock:).

It gave you series humbucking, single coil and parallel humbucking all out of one pickup. Kinda cool. I really only use it as a series/parallel switch though. :wink:
 
I see 'DP3T' and 'DPDT on-on-on' in various catalogs, and thought they might be the same. I got DPDT from the parts list of the piece in question, and Mouser still lists it as DPDT on-on-on.
 
It's weird, huh? Seems like it should be called a SP3T switch. Must be because of the form.
There's a 4P3T version too, Which is the "double pole" equivalant. :?
Edit: Must be considered double pole because you still need to add an external jumper between the poles to get it to function.
 
They are handy. I use those for headphone boxes, wired up so that one position is mono L (sends L signal to both ears), middle position is stereo, and third position is mono R. That way you can easily switch a stereo cue into two mono cue sends if you need more cue mixes while tracking.
 
Oh yeah, I found these in some old console strips I junked. I think I used one as GSSL :mad: sidechain HPF switches: off-80Hz-160Hz or so.. Very handy.

I've never seen them in any cataloques.
 
Was ordering some of these for a 3 way toggle gain switch, and remembered this old post.  Here's a catalog screen capture to illustrate.  Pretty handy when there's no room for a rotary.    One of these is Mouser part #633-M202401-RO

4632337086_7a4d38dfa9_o.png
 
I built my DIY home audio power amp into an old WE PS chassis (back in the '70s). It had an odd 3 position power switch, where I ASSume the power supply could be warmed up at the first on stop, before applying full power at the second on stop. 

I kept the power switch and used the warm up first stop to limit the turn on inrush current with a series resistor. I used the second full power on position to short out the current limit resistor and switch my speaker relays to connect the loudspeakers after the amp had settled down.

JR
 
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