If you were at OpenSauce, you may have seen new Youtuber [Sahko] waltzing about with a retrofuturistic peice of jewelery that revealed itself as a very cool watch. If you weren’t, he’s his very first video on YouTube detailing the design and construction of this piece. We’ve embedded it below, and it’s worth a watch. (Pun intended, as always.)
The build was inspired by the delightful amber LED dot-matrix display modules that circle the band of the watch. They go by HCMS2901, but [Sahko] recommends using the HCMS3901 as it’s both more 3.3V-tolerant and easier to find now. A challenge in mounting so many displays was the voltage on the supply rail dropping below the logic level; presumably the newer version does not have this problem to the same degree. Either way we love the look of these little displays and are pondering projects of our own that might include them.
He’s got quite a few wrapped around his wrist, so at full brightness, all these displays draw one amp. That explains why like the LED watches of the 1970s, the default state of the displays is “OFF”. Even with a LiPo pouch salvaged from a disposable vape, the runtime would only be half an hour at full brightness without that periodicity. Luckily [Sahko] included buttons on the band of the watch to activate it and control the brightness so it isn’t always blasting at full. There are also different modes available, including a really cool waterfall effect you can see in the video.
The band is an interesting choice, too: it’s just a flex PCB. There’s nothing backing it, aside from its own stiffeners, which makes us very curious how well this watch would hold up to daily use. There’s no clasp in the traditional sense, either: the band is closed by a 4-pin connector that doubles as both charge and the USB programmer for the stm32u08 microcontroller that runs the displays. Conveniently for a watch, this version of the stm32 has an RTC, so it keeps time as well. We dig the minimalism of this design; it’s a great contrast to the maximalism of wrapping your wrist in displays.
We’ve seen very similar displays on an edge-viewed watch, but a tiny amber LED matrix never gets old. If you wrapping your wrist in all those tiny LEDs is too impractically power-hungry, try using Nixie tubes.
We’re always watching for projects– wrist mounted clocks or otherwise– so if you’ve got the time, please drop us a tip.
Minimum quantities from major suppliers: 160, at $24/each.
Damn. Guess I’ll stick with my Apple Watch for now.
Pretty neat-looking display. Not going to go onto any normal person’s wrist at any point in the future, but I do wonder what kind of equivalent might emerge which uses a continuous strip of that flexible OLED they use for e.g. foldable smartphones. Could be a thing someday. Will not hold up to any normal use, basically a modern version of the lacy French cuffs people used to wear in the 17th century to show that they never had to touch dirt or a shovel.
I mean, it could totally be a robust solid thing. Just have a more solid bracelet inlay, say actual solid metal band with the OLED glued onto it so it doesn’t flex loads and break. A plastic protection layer over the top and you have a pretty amazing OLED bracelet/watch that can withstand daily wear easily.
If anybody fancies giving this a go, you can grab a display here
https://www.aliexpress.com/item/1005005657678409.html
There are flexible eInk screens in simalar sizes that bend too!
I remember back in the 80s there was a show, “Beyond200” (that was on discovery here in the states) showing off roll up e-ink and oled displays
And we have had foldable displays for years now and its still fragile crap, so I wouldn’t hold your breath too long
FTFA: “…it’s worth a watch. (Pun intended, as always.)”
You missed the obvious “for those of you who have time on your hands”
Tch!
I love it and need it.
needs to be in a bracelet style housing like the first seiko “final fantasy” halo watch
[img]https://auctions.afimg.jp/k1028741045/ya/image/k1028741045.1.jpg[/img]