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Connect a NMEA 0183 Talker
A vessel heading input is required for the
antenna to track satellites above 80
°
in elevation.
You can also provide a vessel position input to
serve as a backup to the antenna’s internal GPS.
If you want to supply both heading and position
to the ICM, you can either connect a NMEA 0183
talker that transmits both messages, or connect
two devices using a NMEA data multiplexer,
such as Actisense
®
model NDC-4.
a.
Configure the customer’s NMEA 0183
talker(s) to transmit a compatible message or
messages at 4800 baud (see Figure 42).
NOTE:
The system does not accept messages that
conform to the NMEA 2000 standard.
b.
Make sure the data message(s) includes the
checksum, identifiable by a
*xx
field at the
end of the data sentence (e.g., $HEHDT,123.4,
T
*1F
). Do not exceed a 10 Hz input rate.
c.
Connect the NMEA 0183 talker or NMEA
data multiplexer to the supplied 2-position
terminal strip connector as shown in
d.
Plug the terminal strip connector into the rear
panel of the ICM.
Connect the RF Cables
a.
Connect the RF coax cable labeled “RX” to the
“Rx RF” jack on the back of the ICM (see
Figure 44). Hand-tighten, then tighten with a
7/16" torque wrench set to 20 in.-lbs.
b.
Connect the RF coax cable labeled “TX” to the
“Tx RF” jack on the back of the ICM. Hand-
tighten, then tighten with a 7/16" torque
wrench set to 20 in.-lbs.
Figure 42: Compatible NMEA 0183 Inputs
Data Type
Compatible Messages
True or Magnetic
Heading
$--HDG
$--HDM
$--HDT
$--OSD
$--THS
$--VHW
Position
$--RMC
Figure 43: NMEA Wiring
NMEA
Terminal Strip Connector
ICM
1
2
A
B
NMEA 0183 Talker
Ship’s Heading
GPS
Ship’s Position
Multiplexer
NMEA 0183 Talker
OR
Ship’s Heading
Ship’s Position*
* Heading is required;
position is optional
If you are using LMR-600-75 RF cables, do not
connect them directly to the ICM. Connect the
supplied 1 ft (30 cm) LMR-400-75 pigtail
cables in-line between the RF cables and the
ICM.
IMPORTANT!
ICM
TxRF
RxRF
Antenna
MTx
MRx
Pigtails
Pigtails
(if necessary)
Figure 44: Antenna RF Transmit and Receive Wiring
Continued
Wire the ICM
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