Switching Circuits on/off with pushbuttons that contain leds

[blue_lu]

Hi there,

I am going to build a couple of devices for table top use, so instead of using our standard beloved 3pdt footswitch (*crank*) I would like to use a softer,
better feeling (and looking) alternative. I was thinking about a latching on/off switch containing a LED (indicating off/on). Now the problem for me as serious n00b is: these switches obviously have a very different layout regarding the connections that are made - I don't want the device to be switched on or off literally, but I want the signal to bypass or to pass through the effect, just like a regular 3pdt switch would allow...
Is there an easy way to achieve this - the longer I think about the more certain I am that I will need an additional board for the switching...

Please help and let your thoughts flow... thanks!s

[pjwhite]

Can you post information about the switch you are thinking of using?

[blue_lu]

this one for example:



it is an arcade button that can be equiped with a led. non latching though


or this one


also non latching...


anyone other ideas?

[Mark Hammer]

I have some soft-touch push buttons where a little mechanism inside the button itself moves a little flap such that the button changes colour when pressed.  It is entirely mechanical, and goes from black to bright orange when you push it in.

[blue_lu]

sorry about the information part being so shallow - but all these internet sites offer very little information about how these work.

usually two contacts for the switch and three (don't know why) for the led. I will keep looking. If you have a nice source for illuminated push buttons please share.

[blue_lu]

mark, sounds cool, where did you get them? can you post some pics?

[pjwhite]

Sounds like a relay is the answer.  If the button you want to use is a momentary SPST type, you will need switch debouncing and toggle circuits to drive the relay.  If you have a latching SPST switch, that will make it much simpler to turn a 3PDT relay on and off.  If you can't find circuits for these on the web, I'd be glad to sketch out something that should work.

[blue_lu]

I will look around, but I won't discourage you from drawing something up 

[Mark Hammer]

mark, sounds cool, where did you get them? can you post some pics?

They were surplus. Pics might be tricky, but I'll see what I can do.

[runmikeyrun]

I found a switch at a surplus store that had a build in LED... it was supposed to run on 12v but worked ok on 9v.  I'm sure if you search the catalogs at mouser, MCM, and parts express you'll find something.

[JKowalski]

Use the CD4053. Dual DPDT analog switching IC. A flip flop to convert pulses into state changes and you are set. Check geofex for a more in depth explanation. The LED can be driven from the flip flop output.

There's not really an EASY solution. Relay or 4053 are the only options I think you have, each about as complicated as the other. Definitely need some PCB room for this.

[blue_lu]

kowalski, thanks for the explanation, I will check it out! many thanks!