Operation Manual

3 Installing the SiteNet 450 Network
16 SiteNet 450 Operation Manual
3.1 Introduction
Before setting up the equipment in the field, verify that each
radio-modem is set to the same channel and wireless data rate. Also
verify that the radio-modem’s Data Port settings are 38400 and parity
none. Set the serial port settings for both base and rover GPS receivers
to 38400 bps, 8 bits, parity none, and 1 stop bit. For more information
about general GPS receiver setup information, refer to the GPS
receiver manual. If these settings are not available, use the WinFLASH
utility to set the radio-modem’s serial port settings to those of the GPS
receiver.
Note – High-power signals from a nearby high-power radio station or
radar transmitter can overwhelm the radio-modem circuits. This does
not harm the instruments, but can prevent them from functioning
correctly. To avoid problems, try not to use the radio-modems within
400 meters (1300 feet) of powerful radar, television, or other
transmitters. Low-power transmitters such as those in portable phones
and walkie-talkies normally do not interfere with SiteNet 450
radio-modem operations unless they are tuned to the same channel.
Always monitor frequency before and during operation. Transmit only
on a clear channel.
Also, to avoid possible interference with GPS reception, keep the base
radio-modem antenna as far as possible from the GPS antenna. A
minimum of 3 meters (10 feet) is recommended.
For more information about the precautions when using certain
frequencies that can interfere with GPS operation, refer to Selecting
Communications Radios, page 47. This is a copy of Trimble’s
publication Using Radio Communication systems with GPS Surveying
Receivers (PN 1-612-0082-2/94).
Installation as a Repeater
To achieve coverage to all points in a survey area, a SiteNet 450
network may include up to two repeaters under certain conditions. The
repeaters retransmit data packets in a way that avoids interference
SN450.book Page 16 Friday, October 5, 2001 5:01 PM