Hello Fellas,
Hopefully you'll find this interesting... I constructed this a few years ago... (I think I was 13). After driving my parents to despair over battery usage, my Dad (who's friend was a blinding instrument guy (and they both worked at the local nuclear power station)) helped me design a twin PSU. I built the circuit, he went through with me how to start, research the components etc... (before .pdf datasheets and internet! Had to use RS components and Maplin catalog) and Dad did the drilling and "sourcing" of all the bits etc..
Max voltage output is 25V per channel, 2A per channel can be drawn (or if you bridge the outputs you can get a whopping 4A supply)
Biased on the LM723, this unit has also short-circuit protection, AND you can limit the current going out. Although the gauges are analogue, they still do the job, and I didn't want to mess up the calibration of the dials.
I'm 35 now, and the unit is still in use. Unfortunately, the PSU used to have a nasty habit of discharging max voltage through the output terminals when you turned the unit off (no bleed resistors on the caps!!). When I was an apprentice, I fitted bleed resistors AND relays to disconnect the output terminals (along with additional snubbers etc).
God only knows now where I put the schematic for it... But I'm sure it wouldn't be too difficult to reverse engineer... Hmmmm....
Regards,
Karl