How to reset a clock from 12:00 to 1:00

[FastEddie]

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I am trying to build a retro digital clock using LS TTL logic, My decade counters are 74LS90 for ones of seconds, tens of minutes and tens of hours. The remaining tens of seconds, Tens of minutes, and tens of hours, use a 74LS92. I have the 60Hz reference working and use a 74LS90 (divide by 10) and a 74LS92 (divide by 6) to obtain the one pulse per second to drive the clock circuit. The display decoders are the 74LS247's and the displays are Numitrons.

What I cannot figure out is how to reset back to 1:00 after 12:00 has passed? I have tried various gates to obtain a reset pulse. After about 30 or so hours of trying I am out of ideas and require some assistance.

I am not an EE or Tech person but was a QA Engineer for 35 years. I had two strokes and now spend my spare time tinkering with electronics.

Ed

 

[philba]

sigh. did you try any of the suggestions you got here - https://www.electro-tech-online.com/threads/resetting-a-clock-back-to-1-00-after-12-00.24292/

 

[FastEddie]

sigh... I tried what I was able to do. I have already stated that I am not a EE. I also tried to post about the simple EPROM programmer with no success. I do have a portion of my schematic that supposedly came from a working design (It doesn't work). So I am stuck in the forest and can't see the trees. I have even been searching for the March 73 issue of Popular Electronics for the clock I built in the seventies which worked flawlessly.

 

[gorehound]

Clock Schematic

I did a search on google for digital clock schematic and found this. It is kinda blurry but might be what you were looking for.

**broken link removed**