Receiver Setup As A Temporary Reference Station - Topcon Net-G3 Operator's Manual

• Beyond 30 meters, consider using in-line amplifiers or extra low
loss cables.
Topcon offers 30 and 60 meter cable options using LMR-400 and
a 100 meter cable using LMR-600. For LMR-600 at 1600 MHz,
the attenuation is 0.1 dB/meter.
• The total attenuation of the cable system should not be more than
10–12 dB at 1.6 GHz.
For installation with multiple receivers and a single antenna,
GNSS antenna splitters. The splitter(s) should normally have one RF
output that passes DC current from the connected Net-G3A receiver
through the splitter to the antenna. The other RF outputs should block
DC current to prevent antenna damage. Also, the splitter should have
a minimum of 20 dB RF isolation between its outputs to eliminate
possible interference between the receivers connected with this
splitter.
For applications where power is supplied from a separate
consider using the bias tee. The bias tee typically has two
source,
coaxial connectors and a connector to power the antenna's LNA from
an external power supply. One of the coax connectors is usually
marked RF + DC and will have DC appearing on its center pin. The
other connector is marked RF and it is DC-blocked. The remaining
connector marked DC is where power should be applied.
Receiver Setup as a Temporary
Reference Station
The typical permanent or semi-permanent Reference Station setup
has the Net-G3A in a secure location with access to power and
communication links as required. The antenna location has been
surveyed very accurately and is free of signal obstructions and
interference (RF, multipath, etc.).
As a temporary Reference Station, certain steps must be performed to
ensure proper data collection. The following sections detail the use of
the Net-G3A in a temporary Reference Station configuration.
P/N 7010-0935

Receiver Setup as a Temporary Reference Station

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