Electronic dice Experiment

I have built a schematic on multisim for the required dice experiment I have to perform tomorrow. As I hold the switch the display seems to be switching between numbers but as I let go, the number disappears. Any idea how to fix this? I followed the schematic attached and my multisim is attached also. If youd like to see the file or any deeper questions plz post here or e-mail me atrockstarlivee@yahoo.com thx!

The circuit is working as designed. If the problem is that you can see which numbers are being stepped through then make C1 smaller. If you want the display to be blank during the spin then consider a DPDT spin switch and use the normally closed contacts in the 7 segment ground line.

Mike.

No i like that it cycles through and they are visible. But it never stops on a number like its supposed to...

One problem is that when you release the spin switch, the clock input is left open. You NEVER leave a CMOS input open!!!!! Put a 10k resistor to ground on pin 14 of the 4017.


Edit: I didn't look at your sim schematic before making this comment, just the source sch.

From what I can see this should work. Perhaps I would reduce or remove the 10K resistor on the 4511 pin5 pull down.

I suggest you confirm that the circuit is build as in your simulation, with the 10K pull down on the clock. Then probe your circuit and find out what state the outputs from the 4017 are in when you let go of the button.

a few decoupling caps wouldn't hurt either!