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Digital clock with no ICs

Digital clock with no ICs

The Transistor Clock is made using only discrete components–194 transistors, 566 diodes, 400 resistors, 87 capacitors, and absolutely no integrated circuits. It’s available as an open-source kit from KABtronics. [via Hack a Day]

8 thoughts on “Digital clock with no ICs

  1. Nightstar says:

    Like this!!! Have one I found at a hamfest mid 70’s. It still works!!! Has a stack of board in that case with an external PS to run it.

  2. says:

    This exact project was in the Nuts and Volts July 2009 issue.

  3. john personna says:

    I think it’s interesting for what it shows about modern economies of scale. Transistors are free, but only when they are embedded in a high volume consumer product. Take a $300 netbook, for instance. With a modern CPU and a couple gigabytes of RAM, the per transistor cost is infinitesimal.

    But, back up to single transistors that are almost always now for small scale projects, and you’ve reversed the curve. Then transistors do cost money.

    It makes me wonder about the future. Things like the Arduino may build a commodity following and ratchet up their “free” transistor count. But other things, like 555 timer chips, might level as they reach a static hobby-use share.

  4. Anonymous says:

    what size resistor and cap for a clock using a 555 timer? send to

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I am descended from 5,000 generations of tool-using primates. Also, I went to college and stuff. I am a long-time contributor to MAKE magazine and My work has also appeared in ReadyMade, c't – Magazin für Computertechnik, and The Wall Street Journal.

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