Nixie Tube Frequency Counter

I got this old, beat-up frequency counter for $20 at the Silicon Valley Electronics Flea Market simply because it had a seven-digit nixie tube display. I intended to salvage the nixie tubes and scrap the counter. I half-expected it to blow up when I powered it on, but to my surprise, it actually worked. The thing is built like a tank.

I made a simple pushbutton circuit and hooked it up to the counter; sure enough, it counted the pulses without a hitch.

It's a Fairchild 8220; there is no mention of it on the internet, and no date markings inside the case. The chips inside are "Counter Micrologic," and date from 1966.

The Nixie tubes are National NL-809's, end-viewable. Each is mounted on it's own "Fairchild Count Module."

Видео Nixie Tube Frequency Counter канала Matt Sarnoff