Hamilton Watch Khaki Field Multi-Touch Your watch compensates for temperature, Feet ft, Foot ft

G L O S S A R Y

ALTIMETER

Indication of altitude in relation to sea level

Description of the function

In ALTIMETER mode, your watch is transformed into a barometric altimeter and displays the altitude in

	G L O S S A R Y
Note: "Calibrating" an altimeter means setting it
to the actual altitude of a known point (see the
setting procedure on page 14).	780 m
The values of actual altitudes can be found from
various sources: signs, contour lines and
benchmarks on maps.

relation to the average sea level.

20Explanations

As this instrument is barometric, it calculates the altitude according to atmospheric pressure.

As altitude increases, pressure decreases and vice versa.

2000m

1500m

Miscellaneous information 540 m

Your watch compensates for temperature.

The altitude displayed is therefore corrected automatically. The altimeter makes a measurement every 10 seconds.

540 m

21

Therefore, the altimeter measures the difference in pressure and displays the altitude. It is therefore an ideal instrument for measuring ascents. (e. g. when hiking in the mountains).

1000m

500m

0m P = pressure

Your altimeter will not show the variations in altitude in an aircraft as the cabin is pressurised (constant pressure).

Unit conversion: 1 meter [m]	=	3.281 feet [ft]
1 foot [ft]	=	0.305 meters [m]

Average pressure, at sea level: 1013.25 hPa

Warning!

As pressure is used to calculate the altitude, the altimeter is sensitive to variations in atmospheric pressure as the weather changes. It is not uncommon to see differences in altitude of 100 m in one night.

The value displayed may vary without your altitude actually changing.

Change in weather = variation in pressure = modification of altitude displayed

540 m 540 m

Thus it is necessary to "calibrate" the altimeter as often as possible.

Average variation in pressure and temperature depending on altitude:

Altitude [m] / [ft]		Pressure [hPa]	Temperature [˚C]/[˚F]
	0	1013.25	20	/ 68
111	/ 364	1000	19.3	/ 66.7
988 / 3242		900	13.6	/ 56.4
1949	/ 6395	800	7.3 / 45.2

Technical data

Measuring range:	- 400 m to +9000 m	- 1300 ft to +29500 ft
Resolution:	1 m	3 ft