Hello, I'm trying to make a digital up / down counter.
I got the idea from this site http://www3.telus.net/chemelec/Projects/Counter-UD/Counter-UD.htm
I made a 5 digit counter, see attached PCB schematic, it is identical to the one shown on the site above but has 5 digits instead of 4. At least I thought so. Unfortunately it does not work as expected.
The first digit does not count, it shows a zero.
The counter resets to zeros OK with reset switch, so that part works.
Counting mode is chosen correctly as if I connect ground to other IC pin 9 or 7 it counts on other 4 digits skipping the first.
I think there is an error in my PCB schematic, please help me to find it.
PS What is "Logic supply in this schematic" ?
http://www3.telus.net/chemelec/Projects/Counter-UD/Counter-UD2.png
I'm trying to count by shorting signal ground to UP/down sw1 pins, perhaps this is not how I should use this?
I got the idea from this site http://www3.telus.net/chemelec/Projects/Counter-UD/Counter-UD.htm
I made a 5 digit counter, see attached PCB schematic, it is identical to the one shown on the site above but has 5 digits instead of 4. At least I thought so. Unfortunately it does not work as expected.
The first digit does not count, it shows a zero.
The counter resets to zeros OK with reset switch, so that part works.
Counting mode is chosen correctly as if I connect ground to other IC pin 9 or 7 it counts on other 4 digits skipping the first.
I think there is an error in my PCB schematic, please help me to find it.
PS What is "Logic supply in this schematic" ?
http://www3.telus.net/chemelec/Projects/Counter-UD/Counter-UD2.png
I'm trying to count by shorting signal ground to UP/down sw1 pins, perhaps this is not how I should use this?
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