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HDR-106 MPEG2/H264 – 4:2:2 – 10 bits – DVB-T2/T Diversity 6 – DVB-S2/S Receiver
MANUAL 7.0
A.1 Description
The DC-COFDM down-converter is suitable to work with COFDM digital
links. It translates RF band signals to UHF band. Different down-converter
models are available which can work from 1,3 to 10,5 GHz in bands.
Depending on the DC-COFDM model, the down-converter will be suitable to
convert signals from a concrete frequency range.
The down-converter is designed to work in environments with high
radiofrequency levels. Two band filters prevent the equipment from
receiving and being saturated by strong nearby signals from other services.
An input filter covers the working frequency range.
PHEMT technology and hybrid 3 dB couplers are used to ensure excellent
linearity. Moreover, the down-converter’s excellent noise figure (less than
1.5 dB) makes reception of weak signals very clear.
The local oscillator has an extremely low noise phase and very high
frequency stability. Excellent MER results are obtained in the receiver. This
MER increase due to the local oscillator´s spectral purity enables to increase
link coverage, particularly when there is no direct vision and modulation is
between 16, 64 and 256 QAM.
The amplifier has a good input adaptation.
The Led at the bottom panel shows the working state all time. It shows PLL
unlock alarm and power supply alarm.
The equipment is powered by the receiver. It can also be powered using a
Bias-Tee.
The equipment is waterproof. It can work permanently under extreme
weather conditions.
The down-converter is a very important element in COFDM links, which
require maximum signal quality when using 64QAM or 256 QAM
modulations.