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2 – Hardware Configuration
GPStation™ User Manual 5
CABLE CONNECTION CONSIDERATIONS
The connectors that are used to mate the cables to the GPStation have a locking mechanism which requires careful
insertion and removal. Observe the following when handling the cables.
•
To insert a cable, make certain you are using the appropriate cable for the port
– the COM1/COM2 serial port cable has a different connector (10 pin) than
the I/O cable (8 pin).
•
Line up the red dot on the connector shell with the red index mark on the
socket.
•
Insert the connector until it seats with a click; it is now locked in place.
•
To remove a cable, grasp the connector by the knurled ring and pull (see
illustration). DO NOT PULL DIRECTLY ON THE CABLE.
GPSAntenna CONSIDERATIONS
The purpose of the antenna is to convert the electromagnetic waves transmitted by the GPS satellites at the L1 frequency
(1575.42 MHz) into electrical signals.
The GPStation has been designed for use with the NovAtel Model 501 GPSAntenna as a means of ensuring the highest-
precision positioning accuracy. The Model 501 uses low-profile microstrip technology and include band-pass filtering
and an LNA which is powered directly by the GPStation. It offers exceptional phase-center stability as well as a
significant measure of immunity against multipath interference. To reduce multipath reception even further, the
GPSAntenna can be mounted on an optional NovAtel Choke Ring Ground Plane (refer to the GPSAntenna Model 501
User Manual for more details).
The 501’s low-noise amplifier (LNA) boosts the power of the incoming signals by 23 dB to compensate for cable losses;
if the losses are greater than this, excessive signal degradation will occur and the GPStation may not be able to meet its
performance specifications. The 501 has an environmentally-sealed radome.
NOTE: The performance specifications of the GPStation are guaranteed only when it is used with a NovAtel-supplied
antenna.
When installing the antenna, select a location with a clear view of the sky to the horizon so that each satellite above the
horizon can be tracked without obstruction. The location should also be one that minimizes the effect of multipath (for a
discussion on multipath, please refer to the chapter on “Multipath Elimination Technology” in the GPSCard Command
Descriptions Manual). Ensure that the antenna is securely mounted on a stable structure that will not sway or topple.