Meinberg GPS170LCD-MP - Manual (Page 14)

14
Installation
Power Supply
The power supply used GPS170_LCD_MP see "Technical Appendix" at the end of
this manual.
Mounting the Antenna
The GPS satellites are not stationary but circle round the globe in a period of about 12
hours. They can only be received if no building is in the line-of-sight from the antenna
to the satellite, so the antenna/converter unit must be installed in a location from which
as much of the sky as possible can be seen. The best reception is given when the
antenna has a free view of 8° angular elevation above horizon. If this is not possible
the antenna should be installed with a mostly free view to the equator because of the
satellite courses which are located between latitudes of 55° North and 55° South. If
even this is not possible problems occure especially when at least four sattelites for
positioning have to be found.
The antenna/converter unit can be mounted on a pole with a diameter up to 60 mm
or at a wall. A 50cm plastic tube, two holders for wall-mounting and clamps for pole-
mounting are added to every GPS170. A standard coaxial cable with 50 ohms
impedance should be used to connect the antenna/converter unit to the receiver. The
maximum lenght of cable between antenna and receiver depends on the attenuation
factor of the used coaxial cable.
Example:
Type of cable diameter
Ø [mm] Attenuation at 100MHz
[dB]/100m
max. lenght
[m]
RG58/CU 5mm 15.9 300 1
RG213 10.5mm 6.9 700 1
1)This specifications are made for antenna/converter units produced after January, 2005
The values are typically ones; the exact ones are to find out from the data sheet of the
used cable.
Up to four GPS170 receivers can be run with one antenna/converter unit by using the
optional antenna diplexer. The total length of one antenna line between antenna,
diplexer and receiver must not be longer than the max. lenght shown in the table
above. The position of the diplexer in the antenna line does not matter.
When installing the high voltage protector CN-UB/E (CN-UB-280DC) be aware to set
it directly after reaching indoor. The CN-UB/E is not for outdoor usage.