User Manual

SNB900 Radio Modem User Guide 7
Overview 2
Note – In this manual, CMR™ and CMR+ formats are both
represented by CMR
+.
2.3 Use and Care
The SNB900 is configured as a base or rover, and can be connected to
most Trimble survey-grade GPS receivers through a single serial I/O
cable and power cable. When used as a repeater, the SNB900 operates
autonomously and requires only a power and antenna connection, with
no connection to the serial port.
To achieve line-of-sight (LOS) coverage to all points in a survey area,
an SNB900 radio modem network can include up to two repeaters,
depending on data format and output data rate. The rovers use the data
packet from the base or repeater, whichever the rover receives first.
The radio modem is designed to withstand rough treatment typical of
equipment used in the field. However, it is a precision electronic
instrument and should be treated with reasonable care. It operates at
temperatures from –40 °C to +65 °C (–40 °F to 149 °F). The casing is
sealed and weatherproof.
C Caution – Operating or storing the SNB900 outside the specified
temperature range can damage the instrument.
2.4 Equipment Sets
The SNB900 is supplied as a stand-alone product, but additional parts
are available. For example, additional parts enable you to connect the
SNB900 to a Trimble MS750™, 5700, 5800, R7, or R8 GPS receiver.