[pjungwir]

I have a Raspi and have been researching how to control my sprinklers with it. The old sprinkler control box is flaky, failing, and inflexible, so I'd like to replace it, and it seems like a good excuse for a Raspi project. I have 13 lines, each controlled by a 24 VAC solenoid. The Raspi GPIO pins put out 3.3 VDC. So I need to convert 13 GPIO signals from 3.3 VDC to 24 VAC. If it were one line I'd buy a relay and be done, but I don't want to buy 13 relays. I think a couple of these will do the trick:

http://www.ti.com/product/uln2003a

http://www.ti.com/lit/ds/symlink/uln2003a.pdf

But I'm pretty fuzzy on electronics stuff.

If anyone wants to confirm that I'm on the right track that would be nice. :-)