Goal: use a 556 with diminishing frequency circuit to pulse 2 separate 4017 at different cycles. Breadboard setup works (only with one 4017, it seemed too much for all 3 chips on same board). Soldered it, checked it, rechecked it. Only the 'top' 4017 circuit works when outputs plugged into breadboard leds, cycles as expected. The 2nd 4017 (knight rider) doesn't cycle. It may light only one led, or none. When I remove the board's ground wire from the breadboard, all 5 led light and stay on. I'm using a 12v regulated supply through the breadboard to the board for testing.
Is there an issue with running both 4017 like this in this way on the same board? Can someone please advise what the issue might be, and direct me to keywords and further learning targets?
pdf of the board map attached. Left side is the 3904 to led output, right side the chips are listed. Thank you!
Is there an issue with running both 4017 like this in this way on the same board? Can someone please advise what the issue might be, and direct me to keywords and further learning targets?
pdf of the board map attached. Left side is the 3904 to led output, right side the chips are listed. Thank you!
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