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LGG100-GG Operator’s Manual
75
TR O U B L E S H O O T I N G
Receiver Problems
There are not enough common satellites. In
order to obtain a fixed solution, the Base and
Rover should track at least five common satel-
lites.
Ensure that both the Rover and Base receiv-
ers use the same almanac.
Check the elevation masks of the Rover and
Base receivers; they should be the same.
Poor satellite geometry (PDOP/GDOP values
are too high).
Conduct your measuring when PDOP values
are low. Use the Standalone Mission Plan-
ning tool (http://www.javad.com) to track
DOP values.
The elevation mask is above 15 degrees.
Lower the elevation mask.
The receiver and the antenna have a poor con-
nection.
Ensure the cable is undamaged.
Check the cable connector attachment to the
receiver. Remove and reattach the cable con-
nector to ensure a secure connection.
The Base and Rover modems are set to differ-
ent radio channels.
Set the Base and Rover receivers to the same
radio channel.
A discrepancy exists between the differential
standards used at the Base and Rover receiv-
ers.
Ensure the Base and Rover receivers use the
same corrections input/output format:
Connect your receiver and a computer and
start PCView. See “Connecting the LGG100-
GG and a Computer” on page 27.
Click
Configuration->Receiver->Ports
and
set the same input/output format for both
receivers.
The specified link rate is not compatible with
the link rates the modem supports.
The link rate is the rate at which data transmits
over the RF link.
Change the link rate to that which your
modem supports. See the modem’s manual
for link rate support information.
The specified baud rate is not compatible with
the baud rates the modem supports.
The baud rate is the rate at which the receiver
transmits differential messages to the modem
and vice versa.
Change the baud rate to that which your
modem supports. See the modem’s manual
for baud rate support information.
The distance between Base and Rover is too
far.
Close the distance between the Base and
Rover.
Use repeaters to increase radio coverage.
Table 5-1. Receiver Problems
