I previously wrote about the monitor of my Intel Series II MDS going out, which was because the +15V DC supply tripped the crowbar. The voltage adjust was all the way to the minimum, and the voltage was still about 17.4V with no load, and trips the crowbar with even a small load. I think someone previously encountered this problem and adjusted the pot rather than fixing it, and the problem has gotten worse since.
The root cause of the failure appears to be that the internal voltage reference of the uA723, which is specified as 7.15V ±0.35V, is now 9.4V. The uA723 needs to be replaced. The uA723 is still readily available, but due to the construction of the power supply, replacing it is relatively difficult. Just probing the pins of the chip was a challenge. The pass transistors are mounted to 1/8 inch aluminum plate, but the pins are soldered into rivets in the single-sided PCB, entering from the etch side (which is closest to the aluminum), so they will have to be desoldered to get at the etch side to replace the 723. I considered just cutting the pins of the 723 and soldering another (or a socket) onto it from the component side, but pins 1-7 of the 723 are right next to a big axial electrolytic so there's no way I can solder that side. Input and output wires to the board are soldered into single-pin cup thingies on two opposite edges of the board, so I can't even get the board into an orientation suitable for working on it without desoldering or cutting some of the wires. I haven't bench-tested the monitor, because I haven't kludged up a suitable signal source yet, but I don't think there's anything wrong with it.