David Harmon wrote:
I recently got an ancient monochrome video monitor from a friend.

This thing probably hasn't been powered on for fifteen or twenty years.
I'm thinking I will put it on a variac and turn it up slowly from zero
over several hours, to maybe let electrolytic caps reform, and avoid
anything else that might object to getting suddenly whacked with a full
120 volts. Is that a good idea? Is there anything in a video monitor,
like maybe the high voltage supply, that will object to running on
reduced voltage for a few hours at first?

connect a light globe in the active lead of a power lead and then switch
it on. This technique is useful when repairing/testing monitors.

Andrew