madbeanpedals::forum

General => Open Discussion => Topic started by: midwayfair on November 25, 2013, 06:10:01 PM

Title: Looking for a small 1P3T (prefer toggle, but rotary if necessary)
Post by: midwayfair on November 25, 2013, 06:10:01 PM
I need a switch with three independent throws and a single common connection (to ground).

Asci circuitlet:

|----------|           |
Cap 1  Cap 2    Other thing
|           |            |
   \           \            \

                 |
      G (common connection)

Cap 1 and cap 2 must be disconnected when the other thing is grounded (though they could both be in the circuit together if needed, either in series or in parallel), so I can't use a SPDT center off.

Anyone come across such a thing?

I may have seen a slide switch that had four lugs on it, but I can't remember where. Twould be perfect if there was a toggle like that.

x-posted from DIYSB. I'll update if I hear anything there ...
Title: Re: Looking for a small 1P3T (prefer toggle, but rotary if necessary)
Post by: rullywowr on November 25, 2013, 06:33:05 PM
EDIT:  Drrt..wrong one.
Title: Re: Looking for a small 1P3T (prefer toggle, but rotary if necessary)
Post by: midwayfair on November 25, 2013, 07:13:40 PM
DIYSB to the rescue. Looks like DPDT on/on/on switches don't connect all six lugs in the center.

http://i269.photobucket.com/albums/jj50/walterw2/sp3t.gif

Here's the thread over there: http://www.diystompboxes.com/smfforum/index.php?topic=105180.0
Title: Re: Looking for a small 1P3T (prefer toggle, but rotary if necessary)
Post by: croquet hoop on November 25, 2013, 07:22:15 PM
Just be careful, there are two types of on-on-on DPDT switches, which connect different lugs on the center position:

(http://t1.gstatic.com/images?q=tbn:ANd9GcQL1u-buLX1Z5on2o2iZEQRoDtAFlkBp5wpCUa_FMRTFSEcm41hdC5PX1jhMw)

I think Mark from tagboardeffects used a DPDT on-on-on with a jumper to replace the SP3T on his Riot layout, so if a SP3T is what you need, it looks like the best solution.
Title: Re: Looking for a small 1P3T (prefer toggle, but rotary if necessary)
Post by: CRBMoA on November 26, 2013, 12:46:32 AM
Quote from: croquet hoop on November 25, 2013, 07:22:15 PM
Just be careful, there are two types of on-on-on DPDT switches, which connect different lugs on the center position:

(http://t1.gstatic.com/images?q=tbn:ANd9GcQL1u-buLX1Z5on2o2iZEQRoDtAFlkBp5wpCUa_FMRTFSEcm41hdC5PX1jhMw)

I think Mark from tagboardeffects used a DPDT on-on-on with a jumper to replace the SP3T on his Riot layout, so if a SP3T is what you need, it looks like the best solution.

^^^THIS^^^

I just got bitten by that monster last week. I had 10 switches that did NOT do what I wanted. I figured a work-around, but Croquet Hoop speaks the truth!
Title: Re: Looking for a small 1P3T (prefer toggle, but rotary if necessary)
Post by: midwayfair on November 26, 2013, 03:50:11 AM
The only one that Smallbear carries is the right one, and Slacker over on DIY said he hasn't come across one that worked differently. Do you remember where you saw the wrong ones so they can be avoided?
Title: Re: Looking for a small 1P3T (prefer toggle, but rotary if necessary)
Post by: croquet hoop on November 26, 2013, 04:16:06 AM
I am not sure, I know that both types exist but I think the one Smallbear sells is the most common. If you're designing a board with such a switch, just use this one and add something in the build doc to warn the builder. If you wire it off board, just test the switch beforehand and adjust the jumper location if needed.
Title: Re: Looking for a small 1P3T (prefer toggle, but rotary if necessary)
Post by: haveyouseenhim on November 26, 2013, 08:59:04 AM
Would a slide switch work for you?
Title: Re: Looking for a small 1P3T (prefer toggle, but rotary if necessary)
Post by: midwayfair on November 26, 2013, 12:54:01 PM
Quote from: haveyouseenhim on November 26, 2013, 08:59:04 AM
Would a slide switch work for you?

I did find a four-pole slide switch at mouser, but square holes and round pegs or something like that, you know? :)