Spectra Precision SP80 - Manual (Page 15)

Engl
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9
Height Mark The height mark ([18]) is nested on the shock absorber
diagonally to the front panel.
When the receiver is mounted on a tripod – for use as a base
for example – making a slant measurement to determine the
instrument height is often more convenient than making a
vertical measurement from the ground mark to the antenna
base.
In this case, the height mark can be used to hook the measure
tape (standard accessory) so you can unroll the tape down to
the ground mark and conveniently measure the distance
between these two points. However because the housing of
the measure tape is inserted in the path between the two
points, you should make the following correction to obtain the
real value of slant measurement:
Slant Measurement = Measured Distance + Delta L
Where “Delta L” is the length of the tape measure housing.
Delta L= 0.073 m or 0.2396 ft (2 7/8 inches), as mentioned on the housing.
When the field software requests your input to determine the
instrument height, you will then choose to enter the slant
measurement, rather than the vertical one. The software will
then be able to deduce the real height of the instrument from
the known dimensional parameters of the antenna and the
slant measurement you will have entered.
[18]
73 mm
0.2396 f
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M
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