Picked up aircraft from annual. On subsequent third flight, suddenly got lots of noise on the radios, which then stopped, but then noticed low volts light and ammeter showing serious discharge. Turned everything off and diverted. Still had battery power remaining, and having changed voltage regulator for a new one, could start, but still light on, and no charge happening. System is 14v Cessna. What does the team think? Does the radio noise indicate what happened?
And what to try next?