Ken Shirriff writes:
We recently started restoring a vintage1 analog computer. Unlike a digital computer that represents numbers with discrete binary values, an analog computer performs computations using physical, continuously changeable values such as voltages. Since the accuracy of the results depends on the accuracy of these voltages, a precision power supply is critical in an analog computer. This blog post discusses how this computer’s power supply works, and how we fixed a problem with it. This is the second post in the series; the first post discussed the precision op amps in the computer.
More details at righto.com.