A Watch Only A Ham Can Use

We’re not sure what to make of this one. With the variety of smartwatches and fitness trackers out there, we can’t be surprised by what sort of hardware ends up strapped to wrists these days. So a watch with an RPN calculator isn’t too much of a stretch. But adding a hex editor? And a disassembler? Oh, and while you’re at it, a transceiver for the 70cm ham band? Now that’s something you don’t see every day.

The mind boggles at not only the technical prowess needed to pull off what [Travis Goodspeed (KK4VCZ)] calls the GoodWatch, but at the thought process that led to all these features being packed into the case of a Casio calculator watch. But a lot of hacking is more about the “Why not?” than the “Why?”, and when you start looking at the feature set of the CC430F6137 microcontroller [Travis] chose, things start to make sense. The chip has a built-in RF subsystem, intended no doubt to enable wireless sensor designs. The GoodWatch20 puts the transceiver to work in the 430-MHz band, implementing a simple low-power (QRP) beacon. But the real story here is in the hacks [Travis] used to pull this off, like using flecks of Post-It notes to probe the LCD connections, and that he managed to stay within the confines of the original case.

There’s some real skill here, and it makes for an interesting read. And since the GoodWatch is powered by a coin cell, we think it’d be a great entry for our Coin Cell Challenge contest.

[via r/AmateurRadio]

17 thoughts on “A Watch Only A Ham Can Use

  1. Anyone know why TI discontinued the eZ430-CHRONOS-433 watch? They kept some other versions going longer, but I think the 433 MHz version was axed first. Also CC430 based iirc

    Nice work from Mr Goodspeed (as usual)

  2. Q: “Mr. Bond, here is your new watch.”
    007: “New?”, “They’ve been around since the 1980’s!”
    Q: “Back in the ’80’s they didn’t do RPN, have a Hex Editor and debugger, or a 70cm transceiver.”
    007: “Oh! Does it play Doom?”
    Q: “You will be much too busy on this assignment to play Doom.”
    007: (sigh!)

  3. I have the same model of watch used for the GoodWatch20. About a month ago I was looking for a way to modify it to do RPN, but eventually gave up. This is just what I’ve been looking for, and I think I will be following the project with some interest.

  4. When I was a kid I used to go to a parts store that had a watch with a 2-meter FM transciever built in. I didn’t have the money for it but I always checked it out. The shopkeeper told me it had very little range but with a water tower mounted repeater almost right outside my window that wouldn’t necessarily have been a problem.

    Now I could probaby afford it. But.. the shop closed down. I have tried many times to identify the watch on the internet but all I can find are FMRS watches.

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