Well, this hack has us tickled pink. We love the idea of buying some really cheap piece of technology and doing something amazing with it, and this is a textbook example of that. [davedarko] found the cutest little calculator watch on Ali Express and is working on making a new PCB for it. The plan is to use an ARM processor and Arduino and add a few extras like 24-hour mode and a pink (or potentially RGB) backlight. The new brain will be an ATSAML22G18A, which has an on-board LCD controller and exactly one I/O pin to spare without charlieplexing the buttons.
One of [davedarko]’s primary goals is to keep the LCD and figure out how to talk to it. The first order of business was reverse engineering the watch’s LCD controller by sussing out the secrets from beneath the black blob of epoxy. This was an eye-opening experience as [davedarko] had never worked directly with LCDs before. A strange reading made him bust out the oscilloscope. Long-ish and informative story short, [davedarko] found out that it uses a bias of 1/2 for generating the wave necessary to multiplex the segments and keep the signal alternating. This is definitely one to watch!
We love timepieces around here and have seen all kinds of hacks, especially on Casio watches. Want dark mode? Done. Enable the hidden countdown timer? We’ve got that, too. And have you ever wondered just how water-resistant the F91W is?
There has been an argument raging for years over whether you should design circuit boards with 45-degree corners or 90-degree corners. Why make them with corners at all? This breathtaking circuit board art is from a digital watch circa 1975.
The Pulsar Calculator Watch was the first of its kind and came along with a stylus to operate the miniscule buttons. The circuit board traces would have been laid out by hand, explaining the gentle curves rather than straight lines. The chip-on-board construction is wild, with the silicon die bonded directly to those traces on multiple chips in this image. There is also a mercury tilt sensor on this model that would have switched the display off when not being held up to view the time (or calculate your tip at the Ritz).
We found working models of this watch for sale online for about $225-350. That’s a steal considering the original list price for these is reported to be $550 ($2600 considering inflation).
The beauty of the PCB artwork is hidden away, not just inside the watch case, but obscured by the plastic battery housing to which those tabs on the right are soldered. Think of how many geeks were lucky enough to have one of these and never realized the beauty within. If you’re looking to unlock more of these hidden masterpieces, check out [Greg Charvat’s] article on collecting and restoring digital wristwatches.
Electronics enthusiasts have the opportunity to be on the very cusp of a trend with vintage digital watches (VDW). Vintage digital watches are those watches that from the late 70’s and throughout the 80’s. They’re unlike any watch style today, and for anyone around when they made their debut these deliver a healthy dose of nostalgia.
Monetarily speaking, it is not worth the money to pay a watch maker to restore a digital watch but for those of us with basic electronics skills we can put the time and effort into making them run again and be one of the few in possession of functioning VDW. It’s a statement as well as a sign of your own aptitude.
In the 1950s, artwork of what the future would look like included flying cars and streamlined buildings reaching for the sky. In the 60s we were heading for the Moon. When digital watches came along in the 70s, it seemed like a natural step away from rotating mechanical hands to space age, electrically written digits in futuristic script.
But little did we know that digital watches had existed before and that our interest in digital watches would fade only to be reborn in the age of smartphones.
Mechanical Digital Watches
In 1883, Austrian inventor Josef Pallweber patented his idea for a jumping hour mechanism. At precisely the change of the hour, a dial containing the digits from 1 to 12 rapidly rotates to display the next hour. It does so suddenly and without any bounce, hence the term “jump hour”. He licensed the mechanism to a number of watchmakers who used it in their pocket watches. In the 1920s it appeared in wristwatches as well. The minute was indicated either by a regular minute hand or a dial with digits on it visible through a window as shown here in a wristwatch by Swiss watchmaker, Cortébert.
The jump hour became popular worldwide but was manufactured only for a short period of time due to the complexity of its production. It’s still manufactured today but for very expensive watches, sometimes with a limited edition run.
The modern digital watch, however, started from an unlikely source, the classic movie 2001: A Space Odyssey.
Real quick question: how do you increase productivity at work? The greatest (highest paid) minds would just say: do agile or scrum or something. What’s scrum? That’s where you gather ’round every morning for a waste of time meeting that kills your every desire to be productive. A while back, [Travis Goodspeed] was stuck in some lesser circle of hell like this and in an effort to be polite by not looking at his phone too much, looked at his watch too much. This led to the creation of the Goodwatch, a new bit of hardware that replaces the guts of a Casio calculator watch with a hex editor, ISM-band radio, MSP430 disassembler, and of course an RPN calculator.