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Wobbly clock

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Re: Wobbly clock

#101

Post by bmitc »

jedberg wrote: post #81
agys wrote: post #39

Made me think about the Swiss Railways clock that has the second hand completing the circle in 58.5 seconds; all the clocks on the network then wait for the sync signal from the “master clock". https://en.wikipedia.org/wiki/Swiss_railway_clock

The clocks in my elementary, middle, and high schools would do something similar. Not every minute, but every hour. At the top of the hour, when there was 15 seconds left, the second hand would make 3 second jumps until it hit the top, and then hold until the next hour started. I always thought that was a brilliant way to keep mechanical clocks in sync. And the system had been there since the 1970s, so it was well be…

How did they know when the next hour started without digital communication?

Re: Wobbly clock

#102

Post by ok123456 »

CharlesW wrote: post #91
jedberg wrote: post #83

This clock is great for teaching kids how to tell time! When learning to read a "circle clock", they have a heck of a time understanding what it means when the hour hand is almost but not quite pointing at a number. So when it's 3:45 they will say 4:45 because they know the big hand on 9 means "45" but they get confused because the little hand is almost pointing at 4. This clock solves that problem. Anyone know if I…

> Anyone know if I can get this as an Apple Watch face? Currently, 3rd parties can't create custom Apple Watch faces.

What's the point of a smart watch if you can't change the dial and face however you want? It's like when carriers wouldn't let you load your own ring tones on to your phone, because they didn't want to cannibalize their own ring tone sales.

Re: Wobbly clock

#103

Post by drdaeman »

jedberg wrote: post #83

This clock is great for teaching kids how to tell time! When learning to read a "circle clock", they have a heck of a time understanding what it means when the hour hand is almost but not quite pointing at a number. So when it's 3:45 they will say 4:45 because they know the big hand on 9 means "45" but they get confused because the little hand is almost pointing at 4. This clock solves that problem. Anyone know if I…

If my presumption that analog watchfaces are dying and only used for "classical" looks (as evidenced by all those trendy "artistic" watchfaces that frequently don't even have marks), then I suspect it'll be another lie of a generation, just like I've been told to learn how to do math in my head because "there won't be any calculators around".

I mean, analog watchfaces are bad at telling precise time - it's just that there wasn't anything better until quite recently (and people are typically fine with 5-minute precision). They're great for conceptualizing time intervals (easy to mentally picture a pie chart), but I strongly suspect most people when asked "when is the next meeting?" are reading time then doing the arithmetic rather than reading the interval directly.

I could be wrong, of course.

Re: Wobbly clock

#104

Post by jackson1442 »

ok123456 wrote: post #102
CharlesW wrote: post #91

Earlier quoted context omitted.

> Anyone know if I can get this as an Apple Watch face? Currently, 3rd parties can't create custom Apple Watch faces.

What's the point of a smart watch if you can't change the dial and face however you want? It's like when carriers wouldn't let you load your own ring tones on to your phone, because they didn't want to cannibalize their own ring tone sales.

even stranger since apple doesn't sell faces (with the exception of the Hermes faces which come with purchase of their obscenely expensive watch bands). seems like something they'd just shoot down in review if something got too close to an Hermes face.

Re: Wobbly clock

#106

Post by TJSomething »

jonas-w wrote: post #93
Medea wrote: post #56

Remixed with retina support: https://glitch.com/~noble-gratis-princess

What does "retina support" mean? What is the benefit?

I can't tell, since I don't have a Mac, but looking at the code, it implements a note from the Safari documentation for canvas [0]. I assume that if you don't do this, it either is very small or very pixelated.

[0] https://developer.apple.com/library/archive/documentation/Au...

Re: Wobbly clock

#107

Post by jcrawfordor »

bmitc wrote: post #101
jedberg wrote: post #81

Earlier quoted context omitted.

The clocks in my elementary, middle, and high schools would do something similar. Not every minute, but every hour. At the top of the hour, when there was 15 seconds left, the second hand would make 3 second jumps until it hit the top, and then hold until the next hour started. I always thought that was a brilliant way to keep mechanical clocks in sync. And the system had been there since the 1970s, so it was well be…

How did they know when the next hour started without digital communication?

The details depended on the system. The most common arrangements were either polarity (hour pulse opposite polarity of minute pulse) or a separate wire for hour pulse. Later systems introduced serial digital communications but were never as widely installed as the minute and hour pulse systems in schools.

Re: Wobbly clock

#108

Post by jcrawfordor »

mprovost wrote: post #50
agys wrote: post #39

Made me think about the Swiss Railways clock that has the second hand completing the circle in 58.5 seconds; all the clocks on the network then wait for the sync signal from the “master clock". https://en.wikipedia.org/wiki/Swiss_railway_clock

I love those clocks! But from memory, the second hand gets "stuck" at 12 and then when it moves again, the minute hand advances at the same time. On this one, the minute hand jumps forward at the same time that the second hand goes to 12.

Both systems could be found. Early to mid 20th-century master clock systems were pretty much all designed around a common theme but there were many variations. Some secondary clocks even used fully free-running second hands that weren't synchronized at all and so had no relation to the minute hand advancement.

Re: Wobbly clock

#109

Post by jedberg »

bmitc wrote: post #101
jedberg wrote: post #81

Earlier quoted context omitted.

The clocks in my elementary, middle, and high schools would do something similar. Not every minute, but every hour. At the top of the hour, when there was 15 seconds left, the second hand would make 3 second jumps until it hit the top, and then hold until the next hour started. I always thought that was a brilliant way to keep mechanical clocks in sync. And the system had been there since the 1970s, so it was well be…

How did they know when the next hour started without digital communication?

They had digital communication just not cheap ICs. I don't know how it worked but I imagine it was something like a mechanical switch that held the minute hand until it got a signal from the main office to start moving again.

The clocks could even be set for Daylight time centrally, so I assume it had a way to send a signal that triggered a motor to move the hour hand faster.

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