Which CPU chips run the displays

Spider U6 runs the displays. 7448 decoders Z16 (players 1, 2 and the credit/ball display) and Z17 (players 3, 4) form the digits; Z13-Z15 make the special centre-segment "1"; Z18-Z21 select digits for multiplexing; a driver chip on each display board drives its tube.

Systems

• Gottlieb System 1

Related tips

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• Reviving a faded Futaba display
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Source: Gottlieb System 1 Pinball Repair from 1977 to 1980, Clay Harrell (pinrepair.com)