7400 competition entry: Homemade 7400

Arup entered his Homemade 7400 into the Open 7400 Logic Competition. A video of it proving his concept is available below.

At an earlier post I’ve said that I didn’t have 7400ICs in my drawer.
Surprisingly, the local store was saying 74HC00 out of stock. Hence I decided to make my own 7400 IC.
7400 is a quad two input NAND gate.
Any digital circuit can be made with universal gates like NAND or NOR, even some pretty analog circuits can be made using these as the competition entries show.

Via the forum.

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  1. yeah, this is about at TTl as it gets!
    as a matter of opinion, it May have looked better on a board, but it has a charm all of its own as it is.
    this one gets my vote because I like the mentality behind it, and demonstrates an understanding of the device beyond an anonymous black rectangle with 14 sharp things sticking out of it.
    I guess if transistors weren`t available he could have used Relays instead ;)

    nice engineering Arup !

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