User`s guide

Chapter 4 - Antenna Descriptions

Timing2000 Installation Precautions

The following precautions should be taken into consideration to avoid the introduction of hazards

and adversely affecting performance when installing the Timing2000 GPS Antenna.

• Mounting bracket must be grounded in accordance with the National Electrical Code

Section 810-21.

• Avoid contact with power lines; serious injury could result.

• Avoid making the antenna the highest point on the roof.

• Locate the antenna such that there is a 360° view of the sky.

• Do NOT place any obstructions over or around the antenna.

• For optimal performance, do NOT place the antenna inside a building.

• To prevent ESD damage to the antenna, do NOT touch the center pin on the

antenna connector.

• Use only a 50 ohm transmission line when connecting to the antenna.

• Do NOT apply more than 5 VDC to the center pin of the Timing2000 antenna.

• If more than one receiver is fed by a single antenna, ensure that the receivers are

isolated by a high isolation RF splitter. Low isolation passive splitters can cause sub-

optimal performance.

Timing2000 Antenna Mounting

The Timing2000 antenna is installed with a center-mounting scheme. It uses an industry

standard ‘N’ connector that is incorporated with the Motorola post mount bracket. The minimum

torque to assemble the antenna and custom hex nut on the post mount bracket is 70 kg-cm (61

in-lb); do not exceed 100 kg-cm (86.8 inch-lb). It is recommended that an adjustable wrench with

a minimum opening of 1½ inches be used for this assembly. For optimal performance, ensure

that the base of the antenna is positioned as close as possible to the top of the mounting pole.

Select a mounting location with a clear view of the sky (360°) and use extreme caution when

mounting near high voltage power lines.

It is recommended that the Motorola model MNT62312B1 mounting bracket, designed specifically

for the Timing2000 antenna, be used when installing the antenna. It can be used to install the

Timing2000 antenna to a nominal 1 inch schedule 40 size pipe (approximately 1.6” OD). The four

units included in the mounting assembly are the U-bolt, post mount bracket, lock washer and hex

nut as illustrated in the following figure.

Timing 2000 Antenna in Extreme Weather and Environmental Conditions

To provide additional protection against extreme weather and environmental conditions, a length

of plastic tubing covering the N connector on the bottom of the antenna is recommended to keep

Motorola GPS Products - M12+ User's Guide Revision 6.X 09FEB05