Hacking a Casio F-91W digital watch (2023)(medium.com) |
Hacking a Casio F-91W digital watch (2023)(medium.com) |
Also, no F-91W thread would be complete without a mention of the sensorwatch project: https://www.sensorwatch.net/
I think making a giant Jeff Bezos boat would appeal most to this crowd, but I'd suggest watching them in order.
https://www.unitedartsclubdublin.com/post/bobby-fingers-the-...
Some might even know them without realising it - their incredibly provocative Richard D. James-esque 'Dad's Best Friend', a sonic assault about isolation and toxic masculinity, was featured prominently in the Trainspotting Sequel, "T2"
> Therefore, an ideal antenna should consist of a 22.12 metre long wire, but by convention fractions of λ-lambda (λ/2, λ/4, λ/8, λ/16, etc.) are opportunely chosen.
This sentence is confused enough to be incorrect. λ/2 is generally preferred as an antenna length (standard dipole configuration) because it will resonate at the appropriate frequency with desirable standing wave characteristics (current maximum and zero voltage at input, voltage maximum and current minimum at ends). λ/4 can be used as a half-dipole, but it requires a ground plane to resonate properly. There are also arguments to be made for a 5λ/8 antenna, but none that I'm aware of for λ/8 or λ/16.
In practice for small antennas, physical length and electrical length are only tenuously related, so it's a matter of creating a circuit that acts like an antenna of the chosen length.
https://scribe.rip/infosec-watchtower/how-i-hacked-casio-f-9...
Edit: this comment made sense before the post I replied to was edited to clarify that there is no material difference.
Changing the CSS rule .jb { font-weight: 700; } to .jb { font-weight: 500; } got rid of all the bolded parts for me...
That frankenstein'd chip... no way it can ever be assembled back into a "holder" card without risking everything breaking.
Forget modifying the watch itself. Instead, build a strap add-on to hold the NFC payment chip and antenna.
Here is a project where I did something similar to carry a microSD memory card.
When I did this mod, I soldered the LED on its side, so that it shone directly onto the LCD. This made the watch face much brighter.
On reflection, the similar variant of the watch with an EL display is vastly superior. The A168 is similar to the A158 you mentioned but with a better light.
I recently fitted one on my F91-W and it certainly makes a difference, but it's not going to make the light brighter like some of the other LED mods people have done.
It's a neat idea, to just move the chip. The final result isn't pretty, it would have been way cooler if the whole thing had fitted inside the watch, but there's not a lot of room in an F-91W.
Maybe someone with more experience with antenna designs could find a way to use the backplate as part of the antenna.
I don't know, every time I see someone paying with their watch it looks super awkward when they have to twist their arm so the watch gets close enough to the reader.
Most of the time they are holding their phone in their other hand which makes the whole thing extra silly and unnecessary.
I still think this is a pretty cool project.
While this is really impressive, putting something in front of the faceplate breaks the great F-91W look and feel for me.
Similar project I did to carry a microSD memory card.
I recall the blog n-o-d-e did successfully put an NFC chip inside while also retaining the default PCB, so there is at least some free space in the case...
https://www.theguardian.com/world/2011/apr/25/guantanamo-fil...
OR perhaps your meme is out of date.
More than likely just translation anomalies from Italian to English.
I wear a cheap $5 Chinese made watch only because I use it to carry a backup of all my crucial data with me at all times, even in the shower. If something goes bump in the night, my data is always with me so all I need to worry about is my own personal safety.
https://www.thingiverse.com/thing:6784665
Casio could easily and cheaply add this to their watches and instantly make them much more desirable in my opinion.
https://en.wikipedia.org/wiki/Casio_F-91W#Usage_in_terrorism
But yes, the entire microSD card is encrypted using BitLocker in case it happens to be lost or otherwise falls into the wrong hands. My will contains the decrypt password.
If you think about it, my data is as safe as I am --- if not safer. The authorities aren't going to spend any effort to recover a memory card --- but they will to recover a body with a memory card attached..
Since this is always with me, it serves as the off-site copy in my 3-2-1 backup plan.
See XKCD #538: https://xkcd.com/538/