Published:2009-7-1 4:01:00 Author:May | From:SeekIC
Uses Fairchild FCM7001 IC eauivalent of Cal-Tex CT7001 doek chip (which is no Ionger available) to drive six 7-segment LEDs that can be switched to show 12- or 24-h time and 28/30/31 calendar, along with alarm features. Article gives constluction details.Each SN75491 driver chip has pins 3, 5, 10, and 12 connected to pin 11 through 150-ohm resistor RL is typically 2,7K,chosen to limit LED current to less than 5 mA,－W,J. prudhomme,CT7001 Clockbuster,73 magazine,Dec,1976,p 52－54 and 56－58.
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