RTK Setup Guide
The following is a
concise step-by-step guide to setting up the Trimble equipment for RTK
surveying. It does not cover the theory of operation; these instructions are
much more useful after an introduction to the system.
Rover setup - do this after the base station is running
1.
GPS receiver
1.
Place 2 charged
camcorder batteries in the holders at the bottom of the rover backpack.
2.
Connect the battery
cables to the batteries, and use the Velcro straps to secure the batteries and
cables in place.
3.
Strap receiver into the
backpack, upside down. Use the lower set of straps, which have 2 black foam
pads underneath.
4.
Connect the battery
cables to ports #2 & #3 on the GPS receiver.
5.
Thread the radio antenna
cable through a top cable pass-through, and attach the antenna mount to a brass
threaded mount on the backpack. (The radio cable is normally left in the
backpack, so this step is normally skipped.)
6.
Connect the radio
antenna cable to the GPS receiver.
7.
Attach the radio
antenna, with the correct tip (0dB or 5dB).
8.
If not using the 2m
range pole, attach the GPS antenna to the 3rd piece of the radio mast, and
attach that to the other brass mount on the backpack.
9.
If using the 2m
range pole, attach the antenna to a Quick-Connect shaft, and attach the
quick-connect to the assembled range pole.
10.
Thread the GPS antenna
cable through the other top cable pass-through and coil neatly above the
receiver. Do not kink the cable. Connect the 3-shell Lemo [large] to the GPS
receiver, and the coaxial connector to the antenna.
11.
Connect the data
collector I/O cable to receiver port #1.
12.
Thread the data
collector I/O cable through the lower pass-through on the same side as the GPS
antenna cable. Connect to the data collector.
13.
Tie down loose cables in
the pack, and zip it closed.
14.
Put on and adjust the
pack for a comfortable fit.
15.
Turn on the data
collector (and hence the GPS receiver).
16.
Measure vertical height
of the antenna; this is measured to the bottom of the antenna mount, and can be
done with the Height Rod. Check that the measurement type is correct.
2.
Start the rover
measurements
1.
Make sure that the
correct Job is selected on the data collector. New Jobs may be defined in
the Files mode.
2.
On the hand controller,
choose Survey, and then choose the appropriate Survey Style;
typically Trimble RTK or a custom style. New styles may be
defined at this stage, or in the Survey Styles option in the Configuration mode.
Be sure to choose the same style as for the base station.
3.
Choose Start
survey.
4.
Choose Measure
Points, Continuous Topo, etc.
5.
When measuring points
(of any type), the Rover will attempt to initialize on-the-fly (OTF). This can
only be done if 5 or more satellites are visible and tracked by both the rover
and base station.
6.
When the radio link is
locked, and the receiver has completed the OTF initialization, the status line
on the data collector will have estimated uncertainty and "RTK Fixed"
displayed. You can know begin measuring points.
7.
If less than 5
satellites are visible, it is possible to initialize on a known point. However,
the data quality is liable to be poor due to the low number of satellites. It
is often advisable to change locations or try the survey at a later date with
more satellites.
8.
For all GPS surveying,
try to keep the PDOP < 6.0 - the best yet seen was 1.7 (8 satellites in open
terrain), and PDOP tends to average about 3.0 with 5 or more satellites.
