Timex W253 Watch User Manual


 
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E
a compass uses a declination angle setting. Westerly declinations are subtract-
ed from the computed compass heading while easterly declinations are added.
See the table on pages 24 and 25 for a list of declinations for major world
cities.
Digital:
As it relates to watches, digital tells time with the use of numbers.
In Hg:
In Hg stands for Inches of mercury, which is a unit for measuring air
pressure. One inch of mercury is equivalent to 33.86 millibars.
Lap:
Lap time records the time or duration of individual segments of your activity.
Magnetic North:
The direction of the earth’s magnetic pole and the direction
towards which a compass needle points, which differs from true north (see
below). The difference between true north and magnetic north is used to
calculate the declination angle used by the watch’s compass.
MB:
MB stands for millibars, which is a metric unit for measuring air pressure.
One millibar is equal to .0295 inches of mercury.
Sea Level Pressure:
Air pressure for a specific location adjusted for difference
in the altitude of a location. Typically, local pressure will be lower than sea level
pressure because air pressure decreases with altitude.
GLOSSARY
This glossary provides definitions for some of the features and functions of the
watch described throughout this manual.
Altimeter:
An instrument used to determine the altitude of an object with respect
to a fixed level. Typically altitude is measured with respect to sea level.
Analog:
As it relates to a watch, analog tells time with the use of hands.
Barometer:
A barometer measures atmospheric pressure and can help predict
changes in weather.
Barometric Pressure:
Air pressure as it relates to weather forecasts. Higher
pressure usually indicates warmer and clearer weather while lower pressure
typically indicates cloudy weather and a greater chance of precipitation.
Calibration:
A technique to improve the accuracy of the compass, altimeter,
barometer, and weather forecast, primarily by compensating for local conditions.
Chronograph:
The chronograph records timed segments for the duration of your
activity.
Declination:
To account for the difference between true north and magnetic north,
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