7400 competition entry: Pen holder

Here is an interesting, but unusual entry: Pen holder

I will admit that this may be an unusual project to enter, however as far as I can tell, it does not actually break any rules. It is a functional device in which the circuit (board) is mostly 7400 logic chips.

It appears that it will run indefinitely without needing to change the battries. We love it when we see peoples geek out on display.

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  1. well with cheap fpgas, and MCU they ‘the 7400s’ are starting to feel like electron tubes of old, so this might not be soch a bad use for them.:D.

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