It would be a waste to have perfectly functional prototype parts sitting in a box somewhere. If they’re going to sit in a box, might as well have them sit in a box keeping the time. This might not make any sense unless you check out the page for the Digital Clock 1.0 project. It uses the same schematics, with the exception of the new set/run feature.

I had so many prototype parts left over from the first clock project, that I decided to make another clock from them. This gave me a chance to implement a new idea for a more advanced time-setting circuit using a relay.

New Set/Run Schematic



I combined the old hours and minutes prototypes that were left over from the Digital Clock Version 1.0 build.



I built the new Set/Run Assembly.



Completed a new display.





I then started adding the components to a wooden box that I had. I cut out holes in the back for the set switches and power.

I ran the various cables to where they needed to go and dropped in the bridge.



Bridge rectifier:



I dropped in the time setting circuit and display.



Lastly, I dropped in the hours and minutes sections and wired up the display.



It’s a tight fit, but it works. I let it run for 3 days next to my Timex and it kept time.



Power goes in the back via an adapter. There’s a power switch and the switches for set/run and hours/minutes.



It’s nothing pretty. It could use a paint job and maybe some colored glass for the front, but it works.