Sorry to be a pain but would this work?
I would prefer a 24 vdc output as all my existing relays and solenoids are 24 vdc.
As I see it all output from the opensprinkler would be converted to near perfect 24 vdc
by C1 and D1 and then D3 and D4 would stop the backwash of current from either power source
thus solving the LED issue I originally had.
Although unintended there exists a possibility that the same circuit could be powered from 2 power sources
at the same time, through accident, but is this a great issue with DC???
The system would be intended to drive only the solenoids or relays anything requiring more than 50 mA would be switched via relay.
I hope you guys could add your wisdom and point out the flaws cause I am a REAL amateur at this.