Thanks for your reply.

Just long enough to send 68 bits and get back 68 bits and resend if no response. I found a 1F super cap... How can I prevent other components from draining the cap so that the pic, transmitter and reciever are the only draw? Also would such a cap act as a short for the initial charging? Also what is the easiest way to sense that the ac line no longer has current on it?

My origonal thought was to put a 5M resistor straight in to the pic. Have an onchange interrupt zeroing out a counter. Then having Timer1 incrementing that same counter. If I get 0V on the pin after 10ms (from the counter) start the transmitting till we die sequence.

Currently I don't have a power supply worked out. I was planning on using something simple like: Transformer to 8VAC -> Recitifier -> 100 uF cap -> resistor -> Zener Diode 5.1 -> 470 uF cap. Or maybe use a 7805 if the zener diode doesn't work out.