NavCom Technology GPS Products, User Manual

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SF-2050 User Guide - Rev. E
GPS Antenna Connector
The connector used on the SF-2050 is a TNC female,
labeled “GPS ANT” on the front panel of the sensor as
shown in Figure 2.
‡
The center pin of the TNC connector carries a voltage
of nominally 4.6 VDC, which is used to power the
preamplifier in the
GPS
antenna. When the
GPS
unit is
powered on, the antenna cable should not be
disconnected.
The cable length between the SF-2050 and the Tri-
Mode antenna should not exceed more than 10dB loss
at 1.5GHz. Examples are:
Cable Type Maximum Length
RG58/U 13.7m (45ft)
LMR400 59.7m (196ft)
NavCom cable P/N 94-310058-3012 provides a 3.6m
(12ft) length of RG58/U cable with a right angle male
TNC connector to a straight male TNC connector
suitable for connecting the SF-2050
GPS
sensor to the
Tri-Mode antenna.
In-line amplifiers suitable for all
GPS
frequencies may be
used to increase the length of the antenna cable, but
care should be exercised that tracking performance is
not degraded due to multiple connections, noise from
the amplifier, and possible ingress of moisture and dust.
‡
The antenna cable can degrade signal quality if
incorrectly installed, or the cable loss exceeds NavCom
specifications. Care should be taken not to kink, stretch
or damage the antenna cable. Do not place the cable
adjacent to cables carrying electrical power or radio
frequencies.
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