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just an Alarm Clock


Floradude

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Note that electric clocks tend to run fast because the normal 60Hz is higher than that here. It also makes the electric meters run a bit fast. Surprised?

How much is your digital electric clock off by in a day or a week?

No place on the earth has exactly 60 hz, so, to keep digital clocks happy, the power company guys look at a count of the pulses for that day (2:00 AM is typical for the USA), and they add or subtract pulses (briefly tweaking the frequency) to get the exact number of pulses to give the equivalent of 60 hz for the entire day. Digital electric clocks based on the 60 hz system, then shift forward or hesitate, to match the correct time. Why? Old-school digital electric clocks are simply counters, that count the pulses in the supposed "60 hz" AC waves, and they report "1 minute" elapsing for every 3600 pulses counted.

This means that if the power company uses official UMT times from atomic clocks to adjust their pulse counts every day, then your cheap digital electric clock is as accurate as an atomic clock - because the power company adjusts the pulses to match those calculated from actual UMT atomic clock based times. e.g. We are at UMT -6...

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If you are in Ajijic, there is a "general store" on the south side of the Ajijic Plaza, which we refer to as the dollar store, just east of Bancomer on the corner of Privada Parroquia/Hidalgo and Colon. They have a bit of everything and I have seen digital alarm clocks there. I have one and it does tend to run a bit fast because of the electricity here, but I adjust for that in my mind and when the power goes out completely in the house and I have to reset all the electric clocks, e.g. microwave, stove, etc the alarm clock gets reset based on the current time on my computer.

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Out of 6 or 8 that I have, only one gains time, and only when the power goes off and the battery kicks in. However, I like to have a couple of battery powered so when the CFE goes wonky I don't have to reset them. Most battery are "clickers" one second at a time, but I got one recently at Costco that is a battery, but continuous sweep second hand, really neat, works great.

And, I have a meter that shows frequency and I've never seen it at anything but 60 dead on. Now, if you really want a basic clock then go to http://www.albinoblacksheep.com/flash/clock

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Any electric clock I have owned to include those in my microwave oven gain a minute or two per month, here in upper Ajijic. Why? Because our electric cycles per second average just slightly more the 60 CPS. What is funny is that if you have a CPS meter is that at my Ajijic home, it varies from about 59.9 to 60.1 CPS. Up north where I live it is always a stable 60 CPS.

Even my Kill-A-Watt meter often shows other than 60 CPS. My other two meters are built into my solar power DC to AC inverters and also change

I too am looking for a clock, one that is electric but with bigger digital numbers so that I can see same at night without putting on my glasses.

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