My long-term memory for short-term events could be entirely wrong on this, but I recall working on some 3528As (all ultimately junked out) long ago, and vaguely that there's an "electronic" power switch function in there. IOW, there's a thyristor circuit or relay or something so the power switch on the front is at low voltage, and remotely activates the circuit. I remember thinking it was ridiculously complicated, had lots of problems, and would be unreliable, which was part of the decision process to junk them out - not worth the trouble. I was highly unimpressed with the design and build quality of that product.
Again, I could be all wrong here and may be thinking about something else, but you should thoroughly study the power supply schematics and understand how it all works before digging in too deeply. Good luck.
Ed
