Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Casio-F-91W die-shot

zeptobars.com

Post reply on HN
Print view View original

101–110 of 167 posts

Re: Casio-F-91W die-shot

#101

Post by nightowl_games »

vasqw wrote: post #12

I bought one of those recently and I was surprised by how inaccurate it was. It drifted like 15 seconds every month. From what I've been reading, that is normal, but I was surprised - with all the technological advances that we have it is odd to think that cheap timekeeping is not a solved problem yet! Also: how is the software of these watches without a CPU designed? Is it something like Verilog or whatever?

Anecdotal but my F-91W is currently 8s behind my phone, which I sync'd together about 6 months ago. I've always felt very impressed with how accurate it is.

Re: Casio-F-91W die-shot

#103

Post by [deleted] »

stoppingin wrote: post #92

Apologies for a silly question, what exactly are we looking at here? I've seen the inside of an F-91W, and I always imagined that under the black epoxy blob was some kind of off-the-shelf microprocessor (most likely 4-bit) with a mask ROM containing the watch's logic. Is the entire watch run from this IC, with no processor? If so that's really interesting.

[deleted]

Re: Casio-F-91W die-shot

#104

Post by wkat4242 »

panza wrote: post #94
low_tech_punk wrote: post #90

From the business/design/technology POV, why is this watch so successful and so iconic?

It's durable, keeps good time, battery lasts 7-10 years, clear display, thin and light. It's incredible value for $15-25. Deserves to be as popular as it is.

The only real drawback is the terrible backlight which is fixed by the F-105W which has a soft blue EL backlight <3. Much preferable to the 91 IMO. Functionally both watches are the same.

Re: Casio-F-91W die-shot

#105

Post by xattt »

smackeyacky wrote: post #59
Tor3 wrote: post #25

Earlier quoted context omitted.

At around 1976-1977 I bought one of those fancy new LED wristwatches, where you pressed a button and the time lit up in red. Straight out of James Bond, as I recall. As I was studying electronics at the time I brought the watch to the lab and opened it and connected a frequency counter to the oscillator, you could clearly see the crystal and a little trimming pot (I don't remember by now if that was a pot or somethin…

Get a Casio G-Shock. The 800 models can sync with your phone and the time is auto corrected. I bought a GBA-800 from a pawn broker - out of the dozen or so watches in my box it's the one I reach for if I have to know what time it is accurately.

One of my best bang-for-the-buck purchases was a Casio Waveceptor watch with a hybrid clock face.

The watch uses the WWVB signal for nightly syncing. However, living on the East Coast means syncing is very dependent on day-to-day atmospheric propagation. When I visit more inland, it works great.

The watch face is solar powered, so I’ve never had to change the battery.

It has since been retired after 8 years of use for an Apple Watch, but I think fondly of the mighty job it did.

Re: Casio-F-91W die-shot

#106

Post by somat »

TedDoesntTalk wrote: post #74
frosted-flakes wrote: post #51

Earlier quoted context omitted.

How does the brighter backlight affect battery life? Doesn't the original model have a 7-year battery life?

I think EL uses less current than an incandescent, which is what the F-91W has. Anyway, the battery life always lasts longer than the band for me. Years. I replace it when the band tears, which is before the battery dies.

Is it incandescent!? I would have expected an led, or at least a process improvement where it was replaced by an led.

Re: Casio-F-91W die-shot

#107

Post by xattt »

Tor3 wrote: post #25
vasqw wrote: post #12

I bought one of those recently and I was surprised by how inaccurate it was. It drifted like 15 seconds every month. From what I've been reading, that is normal, but I was surprised - with all the technological advances that we have it is odd to think that cheap timekeeping is not a solved problem yet! Also: how is the software of these watches without a CPU designed? Is it something like Verilog or whatever?

At around 1976-1977 I bought one of those fancy new LED wristwatches, where you pressed a button and the time lit up in red. Straight out of James Bond, as I recall. As I was studying electronics at the time I brought the watch to the lab and opened it and connected a frequency counter to the oscillator, you could clearly see the crystal and a little trimming pot (I don't remember by now if that was a pot or somethin…

> At around 1976-1977 I bought one of those fancy new LED wristwatches, where you pressed a button and the time lit up in red.

This was the vibe I got when the first pre-always-on Apple Watches were first introduced with Raise to Wake - where you had to actively do an action to see the time.

Re: Casio-F-91W die-shot

#108

Post by TedDoesntTalk »

somat wrote: post #106
TedDoesntTalk wrote: post #74

Earlier quoted context omitted.

I think EL uses less current than an incandescent, which is what the F-91W has. Anyway, the battery life always lasts longer than the band for me. Years. I replace it when the band tears, which is before the battery dies.

Is it incandescent!? I would have expected an led, or at least a process improvement where it was replaced by an led.

It’s still an incandescent, unfortunately. If they changed it to an LED, it might be bright enough to be useful.

Re: Casio-F-91W die-shot

#109

Post by moistly »

TheRealPomax wrote: post #73
ajsnigrutin wrote: post #69

Earlier quoted context omitted.

Well.. yeah. If you bough a samsung phone, and it was full of shitty adware and preinstalled apps, would you expect their tablets, smart tvs and fridges to be any different? And are they?

Yes? And yes? You're asking this like it's a bizarre thing to do, but that's how you think about consumer goods as adult: if you dismiss an entire brand conglomerate because of a single product line, that's an incredibly weird way to think about products. If Samsung phones are bad, don't buy (another) Samsung phone. But when you need a dish washer, and reviews say that Samsung's is the best bang for your buck, their…

I just want to note here that Samsung refrigerators and dishwashers are absolute shit and should be avoided like the plague. Also, their stoves are pretty crap, too, with a self-clean option that destroys the motherboard and blowers.

You'll have a hard time convincing me that their design and manufacturing issues are not endemic across their entire company. Fish rots from the head, etc.

Re: Casio-F-91W die-shot

#110

Post by [deleted] »

[deleted] wrote: post #103
stoppingin wrote: post #92

Apologies for a silly question, what exactly are we looking at here? I've seen the inside of an F-91W, and I always imagined that under the black epoxy blob was some kind of off-the-shelf microprocessor (most likely 4-bit) with a mask ROM containing the watch's logic. Is the entire watch run from this IC, with no processor? If so that's really interesting.

[deleted]

[deleted]
Post reply on HN