Yes, that's far too tight a tolerance for a general-purpose supply, and 5% is probably adequate.

I figured I'd put in something unrealistic and get a rise rather than letting what, to most people, is a rather boring topic go by.

My requirements are pretty modest, but I do want somewhat more than the typical monolithic regulator will do in the output current. The old RC4194 didn't rely on one output to control the other, but the two did interact in some ways, though I really don't remember exactly how, and I doubt it's terribly important at this juncture, as I don't have the luxury of using that device or anything similar, as there isn't anything similar.

I'd considered using separate supplies controlled by digital sources, with MCU monitoring of both voltage and current. However, I do like the "feel" of turning a large knob to control the output voltage, and I like the "look" of a galvanometer to indicate what the relationship between current and current-limit is.

I don't fiddle with this sort of thing much, as most of the tools I've been using were built back in the late early '80's while I was staying at home trying to grow back a missing leg. I guess I had more patience then than I have now.

Dual-tracking supplies are not so much in demand as they once were, and I have wanted to find a reasonable way to deal with that problem. I once saw what appeared to be a simple start, using a pair of op-amps, one buffering and the other inverting the voltage created from a potentiometer, to drive the offset of a pair of adjustable regulators, one positive, and one negative. An interesting issue is contained in your remark, i.e. what the supply should do when one or the other side is driven into current limit.

Since my real needs have probably changed considerably since I started thinking I needed to do this, I'm open to comments and suggestions. I do like the interaction between knobs and switches and the user, as opposed, say, to a menu on an LCD and and cursor keys. The controls are probably much more in your bailiwick rather than mine, however, and that's why I sought to draw you into the process.

RE