Novatel DL-L1 GPS Receiver User Manual


 
2 Set Up
DL User Manual Rev 3 17
4. The receiver provides battery power output (BAT) through COM2. It is possible to turn the supply On or Off using
the VOUT command, see Page 63. The BAT output is the switched output of the input power supply so that 12V
output requires 12V input.
5. RF Port & Cables (see RF Port &Cable, Page 21).
6. Connect an RS232C communication device to one of the serial ports of the DL (see Serial Ports & Cables, Page 20).
For example, this might be a radio modem, for receiving differential GPS messages from a base station. The
supplied null-modem cables are intended for RS232C communications only.
7. Insert a PC Card into the DL (see Using the Removable Flash Memory Card, Page 23).
8. Connect the output of a power source (e.g. battery) to the input power port of the DL (see Power Port & Cable, Page
22). Once power is supplied, the DL turns on automatically, begins an initialization sequence, and then enters low-
power mode. See also System Behavior, Page 27.
9. Exit low power mode by pressing the power button, or if connected via a terminal, by hitting the <Enter> key. If you
are going to configure the unit via DL commands, wait for a MSGA log with a BOOTOK message to appear first.
Otherwise, the DL will begin logging according to the stored configuration.
10. Monitor the status indicators (see Status Indicators, Page 26).
The sections of this chapter give further details on these steps.
CHOOSE THE RIGHT ANTENNA
The purpose of an antenna is to convert electromagnetic waves into electrical signals. An active antenna is required. It
has a Low Noise Amplifier (LNA) that boosts the strength of received signals to help offset the cable losses. The LNA
can be energized directly by the DL, or by another source. NovAtel recommends the use of active antennas only.
The recommended antenna depends on which model of the DL you purchased. Table 3 lists the allowable antenna types
for each of the DL models.
Table 3: Allowable Antenna Types
DL Model Allowable Antenna
DL-L1 L1-only or L1/L2
DL-RT20S L1-only or L1/L2
DL-L2 L1/L2
DL-RT2 L1/L2
GPS satellites transmit at two frequencies, 1227.60 MHz (L2) and 1575.42 MHz (L1). NovAtel offers a variety of
antenna models for GPS-only operation. All use low-profile microstrip technology and include band-pass filtering and an
LNA.
All active GPSAntennas can compensate for up to 13 dB of cable loss. Higher cable loss can be used but you should then
expect an increased degradation in signal strength.
The following are L1-only GPSAntennas:
Model 501 - for use in surveying and other kinematic positioning applications; model A031 choke ring available
Model 511 - for use in airborne, marine, ground vehicle or backpack applications
Model 521 - for use in ground vehicle, backpack, or handheld applications
Model 531 - for use in surveying and other kinematic positioning applications; water proof; model A032 choke ring
available
The following are L1/L2 GPSAntennas:
Model 502 - for use in surveying and other kinematic positioning applications; model A032 choke ring available