Furuno GP-1870F, Operator'S Manual

Page: 150 / 209

13. INSTALLATION
13-2
13.2 Installation of Antenna Unit
Mounting considerations
The antenna unit GPA-017/017S (option) is available for receiving GPS signal with far-
ther sensitivity.
Select a suitable mounting location considering the following:
• Select a location out of the radar beam. The radar beam will obstruct or prevent re-
ception of the GPS satellite signal.
• The location should be well away from a VHF antenna. A GPS receiver is interfered
by a harmonic wave of a VHF antenna.
• There should be no interfering object within the line-of-sight to the satellites. Objects
within line-of-sight to a satellite, for example, a mast, may block reception or prolong
acquisition time.
• Mount the antenna unit as high as possible. Mounting the antenna unit as high as
possible keeps it free of interfering objects and water spray, which can interrupt re-
ception of GPS satellite signal if the water freezes.
• If the antenna cable is to be passed through a hole which is not large enough to
pass the connector, you may unfasten the connector with a needle nose pliers and
3/8-inch open-end wrench. Refasten it as shown below after running the cable
through the hole.
• If the internal GPS antenna is used, be sure there are no obstructions above or
around the display unit.
13.3 Installation or Transducers
13.3.1 How to mount a transducer through the hull
Transducer mounting location
The thru-hull mount transducer provides the best performance of all, since the trans-
ducer protrudes from the hull and the effect of air bubbles and turbulence near the hull
skin is reduced. If your boat has a keel, the transducer should be at least 30 cm away
from it.
The performance of this fish finder is directly related to the mounting location of the
transducer, especially for high-speed cruising. The installation should be planned in
advance, keeping the length of the transducer cable and the following factors in mind:
• Air bubbles and turbulence caused by movement of the boat seriously degrade the
sounding capability of the transducer. The transducer should, therefore, be located
Washer
Clamp nut
Gasket (reddish brown)
Shield
Center pin (soldered)
Connector shell