I have a pretty basic question. I'd like advice for the most economic way to convert 24vac to power an Arduino.
My project concept: I want to run an arduino at my HVAC thermostat to monitor the "on" time. It's a very simple coding/wiring project. Ideally, I'll power the breadboard right at the thermostat (HVAC systems use 24vac) so I'd like a small, breadboard mounted transformer/regulator. The only thing I'm powering off the arduino is an 7x5 LED array. It's not a matter of understanding what I need, I'm just looking for suggestions of the most compact, practical way to do this.
BTW - using a Diecimila right now but will probably switch to a nano mounted to a 3x4" breadboard - I don't want a "finished product" but would be nice if it's a compact design.