Hello.
I'm a first year EE student and i put together this clock from this schematic and website. **broken link removed**. It works by stepping down 60hz to 1 hz and using this as a time base for the seconds, min, and hour using 4-bit counters.
Now the problem that I am having, is that the clock seems to double its freq. and skip once a about 10 or more leds are lit at a time. Starts off fine, counting seconds but once it gets a few minutes lit, it starts counting at about 2hz.
Any hints at tracking down what it is? I ended up decoupling almost all of the IC's thinking it was that but no luck. Would exceeding the power output of the IC's cause it to skip? I have checked it over a few times and there doesn't seem to be any solder bridges or anything.
Any tips would be appreciated. I only have a multimeter with a freq. checker at my disposable to use for testing.
Thanks!