iGage
X9x User Manual
page 12 of 53
Setting Up an RTK Base Receiver
Choosing a Good Location for the Base
The location of your base greatly impacts the success of your survey. There are two primary concerns:
1.
Minimizing multipath and obstructions between the base and the sky
2.
Maximizing the effective range of the UHF radio which is broadcasting corrections to the rover
Any multipath or obstructions at your base will affect every single shot at your rover, just as if they existed at the rover. Your
primary concern should be finding an open location for the base that minimizes multipath (via GNSS signal reflections on hard
surfaces.)
A clear view of the sky above a 10 degree mask is also important. Partially obstructed/masked satellites (through tree branches) are
worse than fully obstructed satellites. Clearance to the South, East and West is most important. Obstructions directly to the North
have the least effect on your RTK and static solutions.
When using a UHF radio, your ability to place the UHF antenna in a high location with the minimum of obstructions to your working
area is also important.
Configuring a UHF Base With External ADL Vantage Pro Radio
Base Radio Battery
iGage does not provide a battery for use with the Base. A suitable battery can be sourced locally. Most deep cycle ‘Marine’ battery
or closed cell battery will work well.
There may be some advantage to a closed cell marine battery like the Optima series:
However at three times the price of a standard Marine deep cycle battery:
The standard wet-cell battery may be a better value.
The duty cycle of the radio in normal operation is about 50% and the radio draws about 8 amps at full output power. So a 9-hour
day requires about 40 amp hours. However the battery requirement is greatly increased for operation in cold weather and the
battery’s capacity is reduced after several discharge cycles.
The less the battery is discharged as a function of its maximum capacity, the more charge cycles the battery will accept.
For these reason, when purchasing a battery for the base:
big
-is-certainly-better.
iGage includes both alligator clips AND lug connectors for the battery. A solid lug connection is best. You will not be able to
broadcast at full power with the alligator clips and you run the risk that the clips will overheat. Deep cycle marine batteries include
terminals that will directly accept the lug connectors and you should use them.
Before plugging in the UHF radio, always insure that the antenna has been connected. Double check that the polarity (RED = +;
BLACK = -) is correct before attaching the power connector.