Clock purchased from Brookstone several many years ago. I don’t remember why I didn’t return it.
There is no way to set the time manually, it is only set by syncing with a satellite (I don’t know which one). If the power goes out and then comes back on, the clock automatically re-sets itself. It automatically re-sets itself for Daylight Savings.
And it is and always has been 10 minutes slow.
When I was using it as an alarm clock I just worked around it, setting for 10 minutes earlier than I actually wanted to wake up. Now I don’t need the alarm most of the time.
Anyone have any idea what could cause this odd but true behavior? Is one of our satellites’ time off? Is this satellite orbiting the sun instead of the earth?
So now I’m curious how the time signal travels over the horizon (I live in San Francisco, which is roughly 1200 miles from Ft Collins). I realize this question reveals my woeful ignorance of physics, but there would be no point in trying to cover that up.
The signal is 60 khz which is 1/10 of the lowest frequency on the AM broadcast band. Low frequency signals travel over the horizon with little problem. Even on the AM broadcast band you can hear stations from a long way off.
Well, actually, not close. You got the mantissa right, but you’re off by three orders of magnitude.
10 light-minutes is 179.88 million kilometers. Or 180 (let’s just round) billion meters.
At that distance, his radio needs to be a bit more than 1.2 AU from Fort Collins. Dunno where that’d put him, other than (for instance) in interplanetary space.
Is there a battery backup? Mine wasn’t a synched clock, but it was a plug in with battery backup. When the battery died, the time was never accurate. Putting a new 9V batter in cleared it up.
I have a wall clock that occasionally and for no clear reason updates to 20 minutes slow. I know a fair bit about digital clock logic and circuitry (did some design work, back in the day), but I can’t figure out how that glitch occurs so precisely.
I prefer clocks that run 20 minutes into the future, anyway.
My car sets its own dashboard clock using the GPS signals, but in the menu system it’s possible to deliberately offset the displayed time from the actual GPS time; presumably this is for people who feel compelled to have their clocks run X minutes fast.
Is there may be something in in your clock’s menu system that does the same thing?
is not entirely correct. There has to be a way to correct for the time zone (the radio signal cannot tell which timezone you are in). I suspect that someone has manually set the clock for ten minutes fast and the clock is maintaining that offset. Without knowing the model of the clock, there is no way of telling how to correct it, but I would look for a reset or mode button of some sort on the clock and fiddle with that.
I suspect it is, because I had a clock with the same problem. It was exactly 12 minutes slow from the moment I set it up (I know I had to set the date, but don’t remember if I had to set time zone. It’s possible.) It was a brand new clock that I ordered from Amazon, and I live alone so no one else was fiddling around with it.
The clock had no battery backup and no reset mode or spot that I could find, either in the manual or by the time-tested “push all the buttons and see what happens” method.
I ended up throwing it away and buying a manual-set clock because the inaccurate clock was driving me crazy.
There is a switch to select the time zone, but that’s all it does. There is another switch to toggle to 24-hour military style time. These switches are hidden at the bottom under a little door.