Tuesday, September 6, 2011

Arcade Pushbutton Light Switch


UPDATE:  If you would like to see different circuit design, have a look at version 2.




I was poking around the internets on Labor day when I came across this.  It is a wall switch intended to replace a boring old toggle switch in your arcade room.  My single arcade machine does not warrant its own room, but I do like the idea of an arcade button light switch.  So, in an effort to get up and do something I made this arcade button switch for switching an extension cord.  I have it plugged into the magnifier with fluorescent lamp on my electronics bench.

Since it was a holiday, I wanted to use only parts I had on hand so that I could finish this project the same day.  Fortunately, I have a pretty large selection of bits that included arcade buttons.  Sadly, I had no triacs, though and settled for a relay instead. 

There are quite a few ways that you could make a set/reset flipflop circuit for this purpose.  I settled on a 555 timer setup with relay.  The flipflop could have just as easily been two NPN transistors, but I felt like reminiscing with the venerable 555 timer

Download the schematic here if you like...



I very slowly drilled two holes in a cover plate.




Circuit assembly began with the relay I had on hand.  I soldered some leads to the normally open contacts on the relay and put heatshrink on the solder joints.  The unused, normally closed, pin on the relay was snipped off flush and insulated with a dab of hot glue.  Otherwise, this pin would have been an exposed hot leg of 110VAC.  Not a huge deal as everything is inside a plastic box, but it is a good idea to do.




Circuit assembly continued on a piece of perf board and was hot glued to the top of the relay which, in turn, was hot glued betwixt the arcade push buttons.




In the picture below, you can see where the hot lead of the extension cord is interrupted by the normally open contacts on the relay.  You can also see a knot tied into the extension cord in the top left of the picture as strain relief. 




Below you can see everything fits into the box nicely.  What isn't too apparent is a pair of black wires coming out of the box too.  I chose to use a wall wart transformer to power my circuit instead of the 110VAC coming into the box as this is just a bench top installation and not an, in the wall, permanent fixture.




Here is a video of the switch in action.  You can see the camera adjusting it's auto white balance as the lamp I have the switch plugged into is turning on and off.




This project was a fun way to spend the afternoon.  It certainly adds some geek cred to my electronics bench.  I think I am more interested in a monostable 555 circuit attached to the relay output, however.  That way, I could turn things on for a period of time and have them turn off automatically, instead of returning a day or two later to find out I left my soldering station on again.

9 comments:

lightswitch developer said...

nice! I was amazed just by looking how things go step by step. Actually, I was looking for other
lightswitch
(somewhat software related), but this got me sitting here and read it 'til the end.

keep it up.

Anonymous said...

great article. i would like to make one but without relay. could you perhaps provide schematic with triac or other method?

Pete said...

Hi Anonymous,

I think this page has a tutorial on what you are looking for. I found this and other circuits by searching for "triac flipflop".

http://knol.google.com/k/electronic-circuits-design-for-beginners-chapter-15#

Good luck!
-Pete

hinder90 said...

I really love this. I had the same idea and I figured someone had already done it and lo and behold there you were and you even provided a great how-to.

I was wondering, have you thought of having a switch that was was a single button toggle switch?

Pete said...

Hi hinder90,

I am glad you liked the post. I haven't thought about making any more switches, but now that you mention it, a single button version does sound pretty cool. I think a latching relay would be useful for such a thing. Latching relay on wikipedia

Anonymous said...

what kind of transformer would you recommend for a permanent installation?

plumbing said...

When installing a light switch, it is important to be aware, first and foremost, of correct safety precautions. This will make the installation proceed much more easily and possibly more quickly as well. There is not much advanced skill involved in installing a light switch, and it can save a lot of money compared to hiring an electrician.

Anonymous said...

Hi Pete,

Do you happen to have a parts list for the parts in the schematic? I see I need two 10k0 resisters but thats all I can make out. Please let me know soon!

Thanks,
Vincent

Pete said...

Hi Vincent,

Which parts are you looking for? I took a quick look at the schematic and it looks like all the values are there.

Also, have you seen version 2? I would recommend building this on instead of the 555 timer based one. Here is a link http://petemills.blogspot.com/2011/09/arcade-push-button-light-switch-redux.html