...The other alternative is to make up a small circuit ...GrizzlyT has a circuit and PCB layout on his site...I'm quite sure he wouldn't mind you using it....
Andy
Not at all....It was just my take on a schematic that has been floating around for awhile.
BTW - You can actually take the "circuit" option in two directions.
The first is the relay based circuit that Andy already pointed out. The alternative is an optocoupler based circuit.
I started doing some work on that, too. You can find it here.
opto drawing I played with it a bit, on a breadboard, but never etched any versions (Mostly to do with the spare parts I had laying around
).
So, there's only the .dwg drawing....sorry!