NorthStar Navigation Class B Transceiver NAIS-300 - Manual (Page 13)

Installation 1
The antenna cable should terminate in a standard marine
PL59 plug fitting. Connect the antenna plug to the
socket on the side of the unit and screw the retaining
collar down. Figure ..
To avoid possible water damage to the transceiver, it is
recommended that all cables are looped to provide a drip
path.
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