6
Nera F77
Continuing the Saturn tradition
FREE ADMITTANCE AT
DECK LEVEL AT LEAST
2 M BELOW RADOME
MICROWAVE RADIATION !
NO ADMITTANCE WITHIN 5 M
Based on
8 W/m
2
Placing the Antenna
Radome type
Nera F77 is delivered either with mast mounted or deck
mounted radome.
See previous page.
The mast mounted version includes a hatch which provides
access for service and repair, whereas the deck mounted
version must be lifted down.
Avoiding obstructions
The antenna has a beamwidth of ±7.5 degrees (at 3 dB points)
and ideally requires a free line of sight in all directions above an
elevation angle of +5 degrees
.
Any obstruction will cause blind sectors, resulting in signal
degradation or even loss of communication with the satellite.
Degradation of the satellite signal can only be completely
avoided by placing the antenna higher than any obstructions.
This is often not feasible and a compromise must be made to
reduce the number of blind sectors and cost of installation.
The degree of signal degradation depends on the size of the
obstructions; the distance to them must therefore be consid-
ered.
Preferably, all obstructions within 3 m of the antenna should be
avoided. Obstructions less than 15 cm in diameter can be
ignored beyond this distance.
Radiation precautions
Passengers should not be admitted in areas closer than 5 m
from the antenna.
However, no restrictions are required when the antenna radome
is installed at least 2 m above the highest point accessible to
passengers.
Personnel should not be close to the antenna for periods of
more than 1 hour per day without switching off the RF transmit-
ter.
Summary of Contents for F77
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