SPECTRA PRECISION FOCUS 2 SERIES TOTAL STATION USER GUIDE
4 –
Routine Measurements
44
[HOT]
key
The
[HOT]
key includes the target height, temperature and pressure, target selection and note input
functions. It is available from any observation screen.
To display the
HOT key
menu, press
[HOT]
.
Changing the height of the target
1. From the
HOT key
menu, press
[1]
.
The
Input HT
screen appears.
2. Enter the height of the target, or press the
Stac
softkey to
display the HT stack. The HT stack stores the last 20 HT
values entered.
3. Press
[REC/ENT]
to return to the Basic Measurement screen.
Setting the temperature and pressure
Atmospheric correction
The speed of light in the air is extremely fast. And it is not a constant, but changes with the
temperature and pressure of the atmosphere. Once the atmospheric correction is set, the
instrument can automatically implement atmospheric corrections.
Even when the instrument is powered off, the atmospheric correction value is still maintained.
The formula for atmospheric correction is: (unit: meter)
If the pressure unit is mmHg: 1hPa = 0.75 mmHg
PPM
273.8
=
0.2900
pressurevalue hPa
(
)
×
0.00366
temperaturevalue
°
C
( )
×
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