

Wristwatch microchip with only discrete semiconductors - ramgorur
http://makezine.com/2015/01/30/masterpiece-of-soldering-you-wont-believe-this-handmade-electronic-clock/

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greenyoda
Original article, posted 16 days ago:

[https://news.ycombinator.com/item?id=8934474](https://news.ycombinator.com/item?id=8934474)

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unwind
A bit annoying that this piece repeats the fundamental mystery of the design:

 _The device runs off of a 12 volt DC adapter, and the clock’s timing is
cleverly inferred from the US standard of running electricity at 60 cycles per
second._

Of course, one major characteristic of DC is that it has no "cycles per
second", so the above makes absolutely no sense. If the clock is fed by a
standard (external) DC supply, it doesn't have access to the cycles of the
main power so it can't rely on those.

I would have hoped that someone writing for Make would react when writing
that, and actually do some journalism and dig up how it really works.

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aftbit
I see some transistors...

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Sanddancer
Yah, one of the mods may wanna change the title. This is made with discrete
semiconductors, but is not just diodes and resistors as there are a bunch of
mps6531 and other transistors in this.

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cs-
Bad title, not a watch for the _wrist_ but would be fun to be miniaturized in
a forked version ./

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mschuster91
Impressive work. I can imagine how it was soldered, layer by layer, but how
was this layouted and simulated?

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mostly_harmless
I imagine this was designed at a higher level, then exploded to smaller parts.
For example, usually a 7-segment display controller is used to translate an
input value to one usable by the display, but it looks like he soldered one up
manually.

Similar to inlining functions in software, but all done manually in hardware.

