I'm trying to get a stable 48 VDC power source with at least 500 mA. I have a power transformer with two secondaries, each with 24 V 0.73 A. The transformer is rated at 35 VA.
What I've tried is connecting the middle lugs of the secondaries together to give me 48 VAC, but it's giving me closer to 52 VAC. After the rectifier bridge it's giving me around 52 VDC, but when it gets to the circuit's power capacitors (680 μF across the power rails), it goes up to around 70 VDC. It's supposed to power an audio amplifier and some extra LEDs.
Is there a way to get a constant 48 VDC from this, or am I better off regulating each of the secondaries on their own to 24 VDC, and then wiring them in series? If so, what's the best solution to get the 24 VDC? I was thinking of using 7824s or something similar.