USING THE ST 4000 ALTIMETER AND BAROMETER
Altitude.
The ST 4000 shows altitude below or above sea level from
-4,000 feet to +30,000 feet in 5-foot increments.
How the Altimeter Works.
The ST 4000 measures altitude by detect-
ing differences in air pressure and displaying this information as
altitude above sea level. The ST 4000 works the same way an
aircraft altimeter does.
Barometer.
There are two kinds of barometers: fixed location and
moving location. Moving barometers are designed to be used at
varying elevations. The ST 4000, like an aircraft altimeter, contains a
moving location barometer. Its reading does not move until you set
it by adjusting the altitude in the altimeter display.
Altitude Offset.
A weather change will produce a change in baro-
metric pressure that causes an offset in the displayed altitude from
the actual altitude. This offset is consistent at any altitude, so, if you
start a hike with the altitude reading 50 feet too high, it will read 50
feet too high at any elevation on your hike. You remove the offset by
adjusting the altitude.
When to Adjust Altitude.
Adjust the altitude when you want precise
altitude readings, such as before hiking or climbing, or when you
want to update the Sea Level Barometer. Adjust at a known altitude
such as at the sea side, a marked summit or pass, or a location with
an altitude reference on a map such as a lake. Home or office make
convenient adjustment points after learning their elevations from a
topographic map.
Adjust once a day when hiking, climbing, or when following weath-
er patterns. You can also adjust altitude in the barometer by enter-
ing a current, local barometer reading from a weather report or
airport weather service. When you enter the barometer reading, the
altitude is also adjusted in the altimeter.
Note:
The analog and digital movements of this watch operate inden-
pendantly. Please set each individually to ensure they are kept in sync.
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