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The buttons on Zenith’s original “clicker” remote were a mechanical marvel
(www.theverge.com)
This is a most excellent place for technology news and articles.
It would have been possible, but it would have been expensive and required electricity to work. The fact that they accomplished their goal with what amounts to a set of tiny spring-powered mechanical bells is a marvel.
I meant it more in the sense of one channel, when shutting down for the night, emitting the "next channel" tone such that every viewer's set would change to a channel that was still broadcasting.