By seeing that there is a lot of interest in TTL technology I will put some schema's on this forum re the building of TTL clocks.
I have to go through my old notes as well but I'm more than happy to help anyone out.
I'm old fashioned in a way that i like the older technology a lot more than the newer PIC IC's which are capable of a lot more for less work I guess.
TTL is robust, power hungry but very reliable.
At home i have various TTL clocks running well over 15 to 20 years with no problems whatsoever.
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divide by 24 circuit.
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divide by 12 circuit, for people who like the AM, PM system.
Both circuits can be built with two 7490's and one (½) 7400 IC.
Very few people can say they've had a micro controller running for 15 or 20 years without a hitch. Given that though, with what they're capable of I still like em better than discrete logic =) Probably doesn't help I was born into a throw it a way society, especially with modern electronics. Once it's 'outdated' it's like a brick. TTL logic circuits are going to be here for a long time to come, and with the ever increasing switching losses of mosfets on high frequency chips TTL and ECL logic are going to come around into the standard view a bit.