Ross SRG-4400, Руководство пользователя

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14–2 • GPS Option SRG-4400 User Manual (Iss. 06)
Before You Begin
Surge Protection
Surge protection may be required if rooftop antennas are being connected, in order to meet the
regulations and standards for lightning protection in the countries where the end-product will be
installed.
Lightning protection means actually a protection of people and buildings. If the antenna is hit by
a direct lightning strike, your least worry should be damage of the GPS receiver. You should
worry about the lightning energy, which can enter the building and directly strike a person or
cause fire. A lightning protection shall be mounted at the place where the antenna cable enters the
building. The primary lightning protection must be capable of conducting all potentially
dangerous electrical energy to PE (Protective Earth). In case of a rooftop antenna, a coax-cable
insert is needed. Ross Video doesn't sell these, but there are many companies, which do. The
antenna on the roof can't be protected against a direct lightning strike. It will just melt if hit by a
direct lightning strike.
Rooftop antenna should be installed by experienced electricians, who are familiar with the local
regulations and standards. Not following these regulations may lead to legal actions and rejection
of insurance coverage in case of damage from lightning. Make sure to choose a lightning
protector with DC-pass and suitable for the GPS frequency range (1.575GHz) with low
attenuation.
Notes on Installing an Antenna
Keep the following in mind before installing your antenna and connecting it to your SRG-4400:
• Ensure the Option Key for the GPS feature is enabled on the SRG-4400. Refer to the
section “ Option Enable Menu ” on page 5-57 for details.
• The antenna must be positioned away from any buildings or surfaces that could cause
reflections to be received by the antenna.
• If you are mounting the antenna on a wall bracket, this assembly must be placed at the top
of the wall, so as to gain a clear view of the sky above.
• The GPS antenna cannot be mounted indoors; not even against a window, even one
without an anti-glare coating.
• Because the coaxial cable has different connectors at each end, be sure to install it in the
correct direction.
• When routing the coaxial cable, be sure to avoid tight corners, where the cable could
become kinked. If the low-loss coaxial cable is being installed, this has a much larger
diameter and is of a stiffer construction than the standard cable, and will therefore be very
difficult to route around tight corners.
• Provide adequate cable strain relief at the SRG-4400.