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I met the Geneva drive when I was trained in servicing IBM 514 and 519 reproducing punches[1], in the mid-70s when these machines were on the way out. A 514 could reproduce a deck of punch cards[2] at 100 cards/minute. A punched card was fed from the "read hopper" and a blank one from the "punch hopper" and moved through the machine under steel feed rollers that were given intermittent rotation by a Geneva gear.

Driven by the Geneva, the feed rollers would move the cards the width of one of their 12 rows, then stop. On the read side, that row was under a gang of 80 little bronze wire brushes. On the punch side, the row was over a gang of 80 sharp little steel punches. When the cards stopped a pulse of current went through the brushes. If there was a hole in the card on the read side, current flowed on to one of 80 little solenoids. The solenoid would yank a bell-crank that pushed a punch through the blank card.

The punches withdrew, the Geneva swung its next lobe, and the cards advanced to the next row. Twelve rows per card, 100 c/m. It was quite noisy despite heavy sound insulation on the insides of the covers, a distinct brrruup, brrruup, brrruup overlaid with a general mechanical roar.

[1]http://www.columbia.edu/cu/computinghistory/reproducer.html [2]http://en.wikipedia.org/wiki/File:Blue-punch-card-front-hori...




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