Why are digital clocks so inaccurate?
From appliances to electronic equipment, I've noticed that these digital clocks lose time faster than a standard automatic Ronda or Seiko movement. For example, my microwave (relatively new) gains about 5 mins/month. There's a digital soundboard mixer I use that loses even more time each month.
I don't know what I'm missing here, but without any physical parts or manufacturing inconsistencies, being purely a digital program - shouldn't they be nearly perfectly accurate? I know keeping time is an afterthought for these devices designed to do other things. But given today's technology, shouldn't this be a non-issue? Why do appliances/equipment lose/gain so much time?
Traveler. Collector. Enthusiast. Passion for music, art, sports and other random things.
My suspicion is that the power supply, by which I mean the line voltage from the wall, is the problem.
I read the question wrong, I thought you were speaking about wall clocks 😂
I don't have that problem. The clock on my stove keeps great time, until the next power outage lol. They're only wrong because I can't be bothered to set the time again. (I only need the timer function)
Many of these appliance clocks use the frequency of the power grid to keep time. They can speed up and slow down a bit due to small changes in the power grid frequency.
The reason is because patek phillipe never shrunk down their master clock system so we could have them in our ovens. Or why do you not just have this beside the oven in your kitchen? This is why we don't have nice things...
Thanks @OscarKlosoff and @gbelleh that's a very interesting point. It makes sense that power fluctuations could affect an internal digital clock. But it surprises me that it would be so off. And I will have to double check the soundboard mixer, cuz I believe it's setup on a surge protector/power conditioner, and it still keeps TERRIBLE time.
So a small watch battery provides more stable power than a wall outlet?
The power grid is A/C. In the US you have the current alternating at 60Hz. The cheapest thing you can do is use that frequency to count your seconds. Most stuff plugged into the wall doesn't care if it's actually running at 59Hz or 61Hz. But you'd lose or gain a second a minute in those situations.
A surge protector or power conditioner usually won't fix the frequency of A/C. They are designed to smooth out peaks and valleys in voltage, not the frequency.
I read somewhere that the federal requirements for power companies to correct and maintain frequency deviations are being eliminated. This could make these clocks lose minutes over time if the systems are not being monitored and corrected. I don't remember the details, but maybe your local power grid isn't being corrected anymore.
Here is a great little video from the UK on how the frequency of the power grid varies just because a popular TV show ends and everyone plugs in their kettles. 😀
https://youtu.be/slDAvewWfrA
The extra load pulls the line frequency from 50 Hz down to 49.7, which is 0.6% error. If that's not corrected it will affect any clock that's using line frequency as a time base.
Thanks @OscarKlosoff and @gbelleh that's a very interesting point. It makes sense that power fluctuations could affect an internal digital clock. But it surprises me that it would be so off. And I will have to double check the soundboard mixer, cuz I believe it's setup on a surge protector/power conditioner, and it still keeps TERRIBLE time.
So a small watch battery provides more stable power than a wall outlet?
A watch battery provides a non-fluctuating stream of 1.5 volts at the cycles-per-second standard.
Thanks you guys, this is is some great info and explains alot. I learned something new today! This site is such a great resource of info, thank you WC community 🍻 And its cool to see old school mechanics beat out digital every now and then 😉
Here is a great little video from the UK on how the frequency of the power grid varies just because a popular TV show ends and everyone plugs in their kettles. 😀
https://youtu.be/slDAvewWfrA
The extra load pulls the line frequency from 50 Hz down to 49.7, which is 0.6% error. If that's not corrected it will affect any clock that's using line frequency as a time base.
On a similar note:
https://youtu.be/bij-JjzCa7o
Good question. I've noticed the digital clock in my car, a ten-year-old BMW is fast, while the digital clock in my wife's five-year-old Honda seems to have a direct line to an atomic clock - that thing is always spot on!
Good question. I've noticed the digital clock in my car, a ten-year-old BMW is fast, while the digital clock in my wife's five-year-old Honda seems to have a direct line to an atomic clock - that thing is always spot on!
Yea, I've always given car clocks a pass thinking being "off" for extended periods affected it. What I didn't understand was how a piece of equipment (whether a low end appliance or higher end digital equipment) that were always plugged into the wall could be so off. And all of them off in different ways - some slow, some fast. Just seemed like an issue that our modern tech should have resolved by now. These answers explain alot.