I would like to put together a circuit that does the following function:
1) You input 24VAC.
2) It outputs 12VDC pulse to drive a 3W, 4Ω latched solenoid, pulse width minimum = 1 second.
3) Once 24VAC is removed, it outputs a negative outgoing 12VDC pulse to unlatch the solenoid.
The idea is to latch and unlatch a DC solenoid from a 24VAC signal which comes from a controller. You might be asking why not use a 24VAC solenoid and just reverse the polarity to unlatch! Well, where I am there's a huge price difference and my customer bought a large amount of these DC solenoids. And don't ask about the weird 24VAC signal ;-)
Looking forward to your responses.