Chapter 2 CPT7 Installation
CPT7 and CPT7700 Installation and Operation User Manual v12
28
A dual frequency capable GNSS antenna is required to use SPAN, RTK, ALIGN or dual
frequency GLIDE.
An L-Band capable antenna is required to receive TerraStar corrections.
For more information about antenna selection, see
Importance of Antenna Selection
2.6 Choosing a Coaxial Cable
An appropriate coaxial cable matches the impedances of the antenna and receiver (50 ohms) and has a line
loss not exceeding 10.0 dB. If the limit is exceeded, excessive signal degradation may occur and the receiver
may not meet performance specifications. NovAtel offers several coaxial cables to meet GNSS antenna
interconnection requirements, including:
l
5 m, 15 m and 30 m antenna cable with TNC connectors on both ends (NovAtel part numbers GPS-C006,
GPS-C016 and GPS-C032)
l
2.5 m and 5 m antenna cable with an SMA connector on one end and a TNC connector on the other
(NovAtel part numbers 60723177 and 60723178)
The CPT7 requires cables with an SMA connector on the CPT7 side or an SMA to TNC adapter.
The SMA to TNC cables (60723177 and 60723178) are not recommended for permanent outdoor
use.
For more information about antenna cabling, including using cables longer than 30 m and in-line
amplifiers, refer to
APN-077: RF Equipment Selection and Installation
available from
novatel.com/support/support-materials/application-notes
).
NovAtel recommends using high quality coaxial cables because an impedance mismatch is possible
when using lower quality cables and this produces reflections in the cable that increases signal loss.
Although other high quality antenna cables can be used, the performance specifications of the OEM7
receivers are warranted only when used with NovAtel supplied accessories.
2.7 Power Supply Requirements for the CPT7
The CPT7 requires a power supply that provides:
l
a voltage in the range of +9 to +36 VDC
l
at least 18 W of power (peak)
See
CPT7 Electrical and Environmental Specifications
on page 172 for more power supply specifications.
