Anyone else find the clock is fast on their 2010?

It would be nice if you could get easy access to the trimmer and fine tune the clock. I have found the consistency of digital time keeping devices over periods of months and years to be much better than their factory or any one time calibration accuracy.

My digital watch I retired after nearly 25 years very consistently gained 30 plus/- a few seconds a month.

In the 1970s I bought one of the first cheap digital watches (about $15 IIRC and made by National Semiconductor) it used LEDs and you had to press a button to read the time. I popped the back off and adjusted the crystal trim capacitor several times and eventually got it to average a few seconds +/- a month. I took it to our cal lab and it wasn't that good at any one time, but it was tuned to me wearing it. A car clock would be harder to get that good because it's temperature isn't moderated by being strapped to a temperature moderating wrist.

Unfortunately, making the trimmer accessible for the one in 52,347 customers who would actually use it would be hard to justify though.

 

As the ghost of grace Hopper holds up a 0.1mm long piece of wire to demonstrate how long a picosecond is...


While verifying the spelling of her name I ran across this in Wiki

 

I never paid attention to the accuracy for my Prius clock until this thread posted. My clock is approx 30 seconds slow when compared to my Verizon cell phone time. A lousy in-dash clock would not keep me from buying a Prius, or any car.

 

Well, I worry about clock synchronization in the telephone network. That's plesiochronous time, so we sweat averages more than instantaneous phase noise, for which we keep elastic stores of $RANDOM size around.

In-lock frequency offsets are in the 1e-11 range; stratum 2 drift rates are in the 1e-10 per day range; and the number I cited, 1.6e-8 is the maximum frequency offset for a Stratum 2 clock. Most of the stuff I work with, when I work with it, is Stratum 3 which is nominally accurate to +-4.6 ppm (parts per million, or 1e-6) and have slip rates that I'd have to look up.

Speaking of oscillators: These days, one doesn't need double-ovened oscillators to get to Stratum 3, there are overtone crystals that can give you that 4.6 ppm accuracy and are pretty small, and can usually do it over their advertised temperature range which can be from -40C to +65C, but you pay more for that. And such an oscillator would probably cost more than your typical alarm clock, anyway.

The fun stuff on the horizon are micro atomic clocks, I think Rubium based, that come in something the size of a 16-pin DIP. They have accuracies in the 1e-9 range or better and drift rates that beat the 1e-10 of Stratum 2. I believe they're available now. They're not cheap but are, I think, capable of being mass produced, which means that price pressure will eventually get them down to maybe $10 or so.

So, how'd you like a wristwatch that gains or loses a maximum of 1 second in a billion seconds? Let's see, that makes it about one second off in roughly 31 years or so!

KBeck

 

Yea.....I have to also say.....since turning it ahead, it's about 1.5 minutes faster then my cell phone.......but that could be because I did not set it correctly in the first place.

For those who are several minutes different.....you guys have to stop parking under those high tension lines......

BTW---Nothing I do depends on the car clock.

 

I'd probably be pretty annoyed once I learned about leap seconds, and discovered that even if the watch only got 1 second off in 31 years, the time of day would have shifted much more (15 seconds in the last 31 years) to compensate for the solar day being slightly different from the 86,400 seconds we normally call a day.