User's Manual

R emote GPS Cable Chapter 3: Cable Descriptions

• The mounting pipe for the RGPS head should be mounted vertically with less than ﬁve

degrees of tilt.

• It is recommended that the RGPS head be installed using the supplied mounting mast and

mounting hardware. Care should be taken to ensure that the RGPS chassis does not come

into contact with any metal surfaces. F ailure to properly isolate the RGPS chassis from

other conductive surfaces can lead to RGPS head failure. The supplied mounting hardware

has been designed to provide the required RGPS chassis isolation.

• P osition the RGPS head to have an unobstructed view of the sky and to minimize the chance

of debris (leaves, dirt, snow , ice, etc.) accumulating on the radome of the RGPS head.

• The RGPS head must have a clear view of the sky , preferably to within 10 degrees of the

horizon in all directions. The total blockage of the sky (due to buildings, mountains, etc.)

should be less than 50%.

• Place the RGPS head as far away from the transmit antenna as possible to avoid RF

interference issues.

• Place the RGPS head at least 15 m away from lightning rods, towers, or structures that

attract lightning. RGPS head damage is usually not the result of a direct lightning strike,

but of a lightning strike on a nearby structure. Also, since a lightning rod is connected

to an earth ground, it can act as a shield and create a shadow that may block or reduce

the signal from a satellite.

• A fter the Base Control Unit (B CU) is powered up (approximately 15 minutes), check the

RGPS signal strengths with the

gstatus

command on the B CU MMI port.

An optimal installation will have at least one satellite (SV) with an RS SI value 50,

and three (3) satellites with RS SI values 45.

A minimal installation should have at least four (4) satellites with RS SI values 40.

• The RGPS head is rated for ambient air temperatures from –40°C (–40°F) to 75°C (167°F),

and has ratings for humidity , shock, waterproof , UV light resistance, vibrations, salt fog,

ESD , EMI, and altitude.

• The RGPS system used for the Access P oint will support up to 1 km (3280 ft.) of overall

cable length from the RGPS head. If a long cable run needs to be broken into pieces,

minimize the number of breaks in the cable.

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PRELIMINARY - UNDER DEVELOPMENT MA Y 2007