The video signals were digital, but they were controlled by analog voltages.

The electromagnet, by moving, then closes a switch that generates a new pulse of analog voltage that moves on down the cable.

These 0's and 1's are then converted into analog voltages.

At the end of the timed exposure, the imager converts the accumulated charge into a continuous analog voltage at the imager's output terminals.

Its control circuitry consisted of dozens of transistors controlling analog voltages.

Instead of impulses, usually the sequence of numbers update the analog voltage at uniform sampling intervals.

Those systems output the length measurements as an analog voltage.

The majority of op amps in a representative setup are summing amplifiers, which add and subtract analog voltages, providing the result at their output jacks.

A random, but known analog voltage is added to the sampled input voltage.

The generated signal could be analog voltage or current or even digital output.