Adding on/off switch to 9V wall adapter?

I have one of these 9V wall adapters for Arduino:

and I was wondering how I would go about adding an on/off switch onto it. I was thinking one of those rocker switches like they have on christmas tree lights or something similar. Would it just be a matter of cutting the cable, soldering a switch on there, and then shrink wrapping it up? I'm not even sure what model number switch I'm looking for or if there's a specific volt/wattage/whatever I would need to use for it.

Anyone have an idea or know what kind of switch would work with this? Thanks!

Your solution would only turn off the 9v which may be all you are trying to achieve, for instance if you merely want to remove power from the Arduino while you change things around. In that case your solution should work - except that you may find that the wires in the cable are hard to deal with. Someone should really come up with a switch-in-a-box where the box has a socket for the power supply cable and a plug to fit the Arduino.

On the other hand to turn everything off to save power you really have to switch the input to your wall adapter. You could use a switched power strip (which is what I do)* although power strips with individually switched outlets are few and far between in the US. Another solution is to move to a more civilized (or is it civilised) country where the power receptacles are switched.


  • Search for "American DJ PC4 Four Channel Power Strip With Lighted Toggle Switches". I got mine through Amazon.

Yeah, it's an Uno so I can't wire a switch directly to it and it's being used in a project for a friend so I wanted to find a convenient way for him to turn it off and on easily, right on the AC adapter. I guess I could get a male and female connector and just plug the 9v into that, add a switch, and then run the bullet connector out again to the one on the Arduino, but that sounds like a lot of bother. I was hoping there might be just a regular switch that I could add onto the cable itself. I'll keep looking. Thanks for the suggestion, though!

Find a Christmas tree light foot-controlled on/off switch, plug your wallwart into that.

I just edited my post with the source for a switched power strip. Look above.


This is what I was thinking of. Lots of variations available.

I was hoping to find something I could wire onto the cord like an inline on/off rocker switch. Something like this, maybe?

Perhaps I just need to take a run down to home depot or radio shack or something and see what kind of switches they haveā€¦

Did you find one?

Leviton plug switch Home Depot, Ace Hardware

Or, similar to what Crossroads posted: extension cord switch.