4017 outputs going low

Thread Starter

magnet18

Joined Dec 22, 2010
1,227
Alright, I'm back and working on my clock, and I got another digit working (almost), but when the digit before it goes to a 5 or higher, it goes blank.
Example-
10
11
12
13
14
_5
_6
_7
_8
_9
20
21
etc...

My first thought was that the clock in line was shorting to the inhibit, but I can't find any shorts or anything... ideas?
 

Wendy

Joined Mar 24, 2008
23,798
Lets see your current schematics. It could be a simple wiring error, or loading on the CMOS outputs (they can't take much). It may even be zapped chips, but at the moment that is bottom of the troubleshooting list.

During the count monitor your DC power supply, make sure it is stable.
 

bertus

Joined Apr 5, 2008
22,922
Hello,

It could have something to do with the carry out signal.
But as Bill also stated, what is the current schematic you are working on.

Bertus
 

Thread Starter

magnet18

Joined Dec 22, 2010
1,227
OK... funny thing happened...
I connected the scope leads to the power supply, both at the pin of the chip and at the rail, (both of which are flatter than western kansas, so they probably weren't the problem), and the problem just disappeared...
I have no idea why, I just looked at again and plugged it in... :confused:
whatever I guess. :p
 

Wendy

Joined Mar 24, 2008
23,798
I don't see how the seconds button and the minutes tag relate. There isn't a gate to combine signals. But this shouldn't have anything to do with your problem, it is just a observation.

You probably have a bad connection somewhere, the scope leads only wiggled things a bit.
 

Thread Starter

magnet18

Joined Dec 22, 2010
1,227
Oh, I need to update that, I was originally going to use the seconds to set the time, but decided to use the unused half of the 4013 to prevent interference issues and to make a fast set option better.

As for the connection, you're probably right, and either it shows back up and I track it down, or it doesn't and I don't worry about it.
meh.
 
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