stuck, need to change graphic on one site from another with a click toggle

I've been racking my brain trying to figure this one out.

I run a very small online radio station, and we have an link that turns on or off the autoDJ with a click on the appropriate link. I've been trying to come up with a toggle/button that will do this for me, and at the same time change a graphic on a completely separate website to a predetermined graphic for on or off.

The graphic on the completely different website can be generated by a php script on your own website

It checks the status of the autoDJ and serves the correct image accordingly