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Hacking a Casio F-91W digital watch (2023)

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Re: Hacking a Casio F-91W digital watch (2023)

#11

Post by dmaa »

fellerts wrote: post #8

Cool project. Tip: acetone will readily dissolve the plastic parts of the card leaving the antenna(s) and chip intact. I believe a few other people have made drop-in PCBs with NFC antennas. Here’s one: https://n-o-d-e.net/datarunner.html Also, no F-91W thread would be complete without a mention of the sensorwatch project: https://www.sensorwatch.net/

The dissolution in acetone is nicely demonstrated here https://youtu.be/NF4VJJKTjy8?t=835 The guy does it in order to be able to pay with a prosthetic eye.

Re: Hacking a Casio F-91W digital watch (2023)

#12

Post by mschuster91 »

The problem with this approach is, every once in a while - I think the bank sets the limit - the card will not accept any NFC transactions at all until a physical confirm-with-pin transaction is made.

That frankenstein'd chip... no way it can ever be assembled back into a "holder" card without risking everything breaking.

Re: Hacking a Casio F-91W digital watch (2023)

#13

Post by scrapheap »

Guestmodinfo wrote: post #7

I want to put a better backlight in my A158W. Internally F-91W and A158W are same.

You can get light spreader kits for the F91-W/A158W that replace the bit of plastic that sits behind the LCD for one that spreads the light from the LED far more evenly than the stock one.

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.

Re: Hacking a Casio F-91W digital watch (2023)

#14

Post by ThePowerOfFuet »

blargthorwars wrote: post #6
ComputerGuru wrote: post #2

I was captivated by the introduction but I only made it halfway through before I gave up. The random bolding and emphasizing of almost every other word really put me off. Also, even though I can see that it's clearly had a ton of human effort put into it, I got a lot of AI vibes from the writing.

You’re absolutely correct! I was totally hooked by the intro—the kind that promises Forbidden Wisdom™—and then I made it about halfway before my attention quietly left the chat. The random bolding of almost every other word felt like getting yelled at by typography. I wasn’t reading anymore; I was flinching. And sure, I can tell there’s a ton of human effort in there, but the overall vibe? Very “AI but with a human s…

It's leaking

Re: Hacking a Casio F-91W digital watch (2023)

#15

Post by netsharc »

ComputerGuru wrote: post #2

I was captivated by the introduction but I only made it halfway through before I gave up. The random bolding and emphasizing of almost every other word really put me off. Also, even though I can see that it's clearly had a ton of human effort put into it, I got a lot of AI vibes from the writing.

Yeah, it's fucking goddamned excessive.

Changing the CSS rule .jb { font-weight: 700; } to .jb { font-weight: 500; } got rid of all the bolded parts for me...

Re: Hacking a Casio F-91W digital watch (2023)

#16

Post by FridayoLeary »

eresonance wrote: post #4
ComputerGuru wrote: post #2

I was captivated by the introduction but I only made it halfway through before I gave up. The random bolding and emphasizing of almost every other word really put me off. Also, even though I can see that it's clearly had a ton of human effort put into it, I got a lot of AI vibes from the writing.

Yeah I agree, I'm wondering if the author's primary language isn't English and they leaned heavily into AI to get this article together. Either way I found the subject cool but the writing hard to go through.

lots of spelling mistakes which is odd for such a meticulously detailed article. I'm going for the theory he's not an english speaker. Op is wrong, it's one of the most interesting things i've seen here in a while and truly in the spirit of hn.

Re: Hacking a Casio F-91W digital watch (2023)

#17

Post by mrweasel »

throwaway81523 wrote: post #3

sensorwatch.net has been around many years.

That still won't do contactless payments, at least I don't think so.

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.

Re: Hacking a Casio F-91W digital watch (2023)

#18

Post by taneliv »

mschuster91 wrote: post #12

The problem with this approach is, every once in a while - I think the bank sets the limit - the card will not accept any NFC transactions at all until a physical confirm-with-pin transaction is made. That frankenstein'd chip... no way it can ever be assembled back into a "holder" card without risking everything breaking.

Yes, at least according to the information I have, the card issuer sets the limit. It's not clear to me if the chip actually has to be physically slotted in for reading it, though. Can the confirm-with-pin step be done without contact, using NFC feature?

Re: Hacking a Casio F-91W digital watch (2023)

#19

Post by ale42 »

FridayoLeary wrote: post #16
eresonance wrote: post #4

Earlier quoted context omitted.

Yeah I agree, I'm wondering if the author's primary language isn't English and they leaned heavily into AI to get this article together. Either way I found the subject cool but the writing hard to go through.

lots of spelling mistakes which is odd for such a meticulously detailed article. I'm going for the theory he's not an english speaker. Op is wrong, it's one of the most interesting things i've seen here in a while and truly in the spirit of hn.

Well, everything in the article (names & places) seems to point out the author is Italian...

Re: Hacking a Casio F-91W digital watch (2023)

#20

Post by netsharc »

NetMageSCW wrote: post #9

I’ve been doing Apple Pay without issue with the phone since it started, and doing it without authentication since the Apple Watch came out. The (very) few issues wouldn’t be fixed by putting the system in a different case. Seems like a lot of work for nothing.

I watch a YouTube series of 2 guys who restored a classic Mini car (putting the running gear of another car into it, adding bells and whistles and more bells and whistles). They've been going at it 12 years, when they could've just bought a modern car. Seems like a lot of work for nothing.
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