User's Manual

RTK Base Station Setup
SH20560,000011B 1908DEC091/1
Base Station Setup
The base station is the most critical part of RTK system.
During installation, care must be taken to ensure the base
has problemfree operation. There are two issues that
are responsible for most problems with a base station:
Shading and Multipathing. If a base station experiences
one of these problems, it could be detrimental to your RTK
operation. These issues are shared with the 900 MHz
RTK system. Mitigation techniques have already been
documented in the standard StarFire iTC – RTK manual
that came with the iTC receiver. This manual provides
detailed recommendations to minimizing these errors.
Base station operating mode can be either Absolute
Survey Base Mode or Quick Survey Base Mode.
Once you have installed the base station receiver,
installing the radio in a location to best maximize the
output, can be a challenge. Below are several options
currently available through John Deere.
•
Leave the RTK radio in its original configuration
attached directly behind the base station receiver.
•
Use PF80821 extension harness [92 m (300 ft.) in
length], moving the radio from the back of the base
station receiver to an elevated position, and running the
harness in between.
NOTE: It is important to use the PF80821 harness
and grounding wire properly according to the
installation instructions. This harness has
built in protection for both your radio and
receiver for unwanted electrical transients
developed on the harness.
IMPORTANT: The antenna must be installed before
the radio module is powered ON.
Avoid water intrusion by keeping the
antenna attached whenever possible.
Removing the antenna while transmitting
may damage the radio module.
IMPORTANT: If using coaxial cable between the
radio and the antenna, you need to use
the lowestloss cable available or you may
suffer RTK radio link range issues.
•
Attach the RTK radio in a secured location and run
lowloss coaxial cable between the radio and the
antenna.
NOTE: When using this option, it may be necessary to
install a highergain antenna and/or the optional
amplifier to compensate for loss.
450 MHz RTK Radio Specifications
Model Number PF81428
Frequency Range 435470 MHz
Bandwidth Options
25 or 12.5 kHz
Modulation
2 and 4 level GFSK
RF Baud, 25 kHz BW 19.2 kbps at L2
RF Baud, 12.5 kHz BW 9.6 kbps at L2
1400 at 25 kHz
Frequency Channels
2800 at 12.5 kHz
Output Power
0.22 W
Sensitivity 110 dBm for 10^6 BER
In/Out Impedance
50 ohm
Operating Voltage
915 V
Operating Temperature 30 to 60° C
Out RF Connectors Female TNC
Control Connector
4pin Deutsch
Every 450 MHz radio comes standard with 2 dBi whip
antenna that has a TNC connection.
450 MHz Whip Antenna Specifications
Model Number PF81464
Gain
2 dBi
Frequency Range 450470 MHz
Impedance 50 ohm
VSWR
< 2:1
RF Connector
Female NType
Length
13.2 in. (33.5 cm)
Always mount the radio antenna vertically to make sure
that the RTK signal is radiating outwards. If the antenna is
at an angle, it may cause the data received at the vehicle
to be lower than expected.
NOTE: The 450 MHz RTK whip antenna, PF81464, looks
similar to 900 MHz and 869 MHz RTK whip antennas.
To differentiate, it has a white stripe near its tip.
153
121509
PN=13