The internal power supply on my Yamaha keyboard was broken while moving house (PCB is nearly snapped in half) and because it's 30+ years old it's not easy finding a NOS part replacement. I've found the schematic for it (attached), but I'm confused on one part.
The output pins are labeled (and what believe they are):
- +12 (+12V DC)
- AG (No idea - assuming ground???)
- -12 (-12V DC)
- +5 (+5V DC)
- DC (DC Ground)
Can someone please clarify the function of the AG for me? I can see it's connected via rectifier diodes to the +12V and -12V rail, but since I only have a basic understanding of electronics, I don't know what it's actually for.
I'm considering swapping in a pico ATX PSU since they're easily obtained and have the necessary +12, -12, +5 rails, but I've got no idea how (or if it's even possible) to wire in this AG. So secondly I'd like someone to clarify if this idea would/wouldn't work.