FRAME AS-UNDERCARRIAGE 4I6901 - Caterpillar

Introduction
This Technical Information Bulletin addresses the antenna placement ( 263-8948 Antenna Assembly , 263-7802 Antenna Assembly , 266-2861 Antenna Assembly ) for the Product Link PL121SR System.Problem
A performance issue has been identified on certain machines that have the Product Link antenna mounted in less than optimal locations.The Product Link antenna provides two separate functions:
receive Global Positioning System (GPS) signals to determine machine location
communicate with Low Earth Orbit (LEO) communication satellitesNote: Certain mounting location requirements must be followed in order to receive maximum benefit from the Product Link system.Parts Affected
263-8948 Antenna Assembly (Stud Mount with 6 m (19.7 ft) cable
263-7802 Antenna Assembly (Magnet Mount with 6 m (19.7 ft) cable
266-2861 Antenna Assembly (Stud Mount with 3 m (9.8 ft)Solution
When selecting a location to mount the Product Link antenna, the single most important item to consider is the view of the sky. The base of the Product Link antenna serves as the GPS antenna. The flexible vertical whip serves as the VHF antenna for communication with the LEO satellites.The base of the antenna should have a clear view of the sky from horizon to horizon in all directions (360 degrees). Refer to Illustration 1. In most cases, the cab roof usually provides an optimal view of the sky with minimal blockages. The Product Link antenna should be mounted so that the flexible whip is always pointed in the vertical position.
Illustration 1 g01229450
Other Mounting Considerations
If the machine on which Product Link is installed has other two-way communication devices installed, keep the Product Link antenna separated from the other transmitting antenna as much as possible while still maintaining a clear view of the sky.