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Old December 19, 2007, 11:26 AM   #15
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Join Date: May 31, 2004
Location: The Toll Road State, U.S.A.
Posts: 12,451
After going through the instruction book (it's not a booklet) last night, I have one comment and two questions:

1. If you don't live within 600 miles of Ft. Collins, Colorado, the atomic timekeeping feature is not likely to work well, except maybe on the clearest of days, and at some point beyond that - somewhere between 600 and 1,000, don't even bother trying to use that feature. I find it very odd that "they" (whoever "they" are) haven't set up a relay system and other transmitters - one for the east coast and one for the west coast, let's say, to allow people anywhere in the continental USA to utilize the Ft. Collins clock.

2. I am quite perplexed at how the altimeter works. The altimeter does not (of course) directly measure altitude - it measures altitude by measuring barometric pressure. And of course it has a separate barometric pressure guage (makes perfect sense how the barometer works). But I do not see how it's possible for the altimeter to have ANY sort of accuracy at all, when it's based solely on barometric pressure, which obviously fluctuates greatly with, ya know, the BAROMETRIC PRESSURE! Which rises and falls with the weather changes/storm systems, etc. I know that there's a relationship (generally) to temperature as well (altitude-pressure-temperature relationship), but I am fairly certain that the watch does NOT take into account temperature when giving an altitude reading, because the temperature, first of all, can obviously vary tremendously depending on what time of year it is, and can also vary by being indoors, and by having the watch on your wrist! So is this thing going to be a very imprecise altimeter, or am I missing something? If it works, how is this possible without GPS?

3. The Compass: Unlike my Timex compass watches, this watch does NOT have any way to allow you to enter the declination angle based upon where you live, and thus adjust for true north from magnetic north. I don't know why it doesn't, and find it a little hard to believe that such a sophisticated watch doesn't allow you to enter the declination angle and make the correction automatically for you. Now, having said that, the watch DOES allow you to enter a manual calibration from a compass known to be correct: You can enter a "bidirectional" calibration if you magnetize your watch and it's fouled up and has no way to take an accurate reading. Or, more importantly for my purposes, you can enter a "northerly" calibration to simply tell the watch what true north is, and it will remember the difference between true and magnetic, and give you accurate readings from then on. But the only way to do this is to "tell it" by lying the watch on a flat surface pointing exactly at true north (using some other accurate compass) and then hit the setting. Fine, I guess, except that this is a pain in the rearend - how am I going to know actual north from a regular compass, when regular compasses also give me magnetic north, not true? Why wouldn't Casio, like Timex, just allow you to enter your "zone" relative to magnetic north, and thus the declination angle and fix the reading for you automatically? Only one reason I can possibly think of for this: Perhaps this is intended this way for the specific reason that, since magnetic north is actually gradually moving along its way, due to plate tectonics, etc., having a static declination angle adjustment feature built into the watch will actually give you INaccurate readings here in 10 or 20 years or longer. So, since I guess they expect you might actually own and use the watch for that long, they opted for just putting in the manual calibration instead.... plausible theory?
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