Vintage Digital Frequency Meter Teardown

You think of digital displays as modern, but the idea isn’t that new. We had clocks, for example, with wheels and flip digits for years. The Racal frequency counter that [Thomas Scherrer] is playing with in the video below has columns of digits with lamps behind them. You just need the right plastic and ten lightbulbs per digit, and you are in business. Easy enough to accomplish in 1962.

Inside the box was surprising. The stack of PC boards looks more like a minicomputer than a piece of test gear. There were a few novel items inside, too, ranging from a glass-encapsulated crystal to an interesting method of selecting the line voltage.

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