Trimble Outdoors SPSX51 - Manual (Page 48)

5 Setting up the Receiver
46 SPSx51 Modular GPS Receivers User Guide
Figure 5.2 System set up on a T-bar showing an external radio antenna to gain longer
range
Setting up a mobile base station: Tripod and fixed height tripod
If you are repeatedly moving between jobsites, or if you are visiting a jobsite for the first
time before a T-Bar or similar setup can be established, Trimble recommends that you
use either a tripod and tribrach setup, or a fixed height tripod.
The fixed height tripod is quicker and easier to set up over a control point. It allows you
to re-establish the antenna height exactly so that the receiver can be set up faster
without using the SCS900 software or without needing to enter a revised antenna
height in the receiver front panel. Take great care to ensure that the GPS antenna is set
up accurately over the control point, and that the GPS antenna height is measured
accurately, in the right way (vertical or slope height) to the right location on the
antenna (base of antenna or to a specified location on the antenna). When you start
the rover receiver, it is extremely important to check in, at one or more known
locations, to check for possible position or height errors. Checking in at a known
location is good practice and can avoid costly errors caused by a bad setup.
Typically, the tripod and fixed height tripod methods do not give significant height
clearance above the ground, and can reduce the range of operation caused by radio
limitations.
Tripod and tribrach setup
In the tripod setup, the tripod is located over the control point, and the tribrach and
tribrach adaptor is mounted on the tripod and centered over the point.
GPS
Radio