Promax HD Ranger +, Руководство пользователя

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December 2014
63
A5.4 Selective optical to RF converter
A5.4.1 Description
The selective optical to RF converter has a filter that separates each wavelength
and directs it to an independent circuit with a photosensor, which obtains the RF
signal that carries. The RF signal obtained for each wavelength passes to a band
switch.
The band switch receives a signal and converts it to a frequency within the RF
band (65 — 2150 MHz). In the case of a terrestrial / cable signal the signal is not
converted since that signal is within the
RF range. After the conversion, the RF
signal output is connected to the analyser input connector and the measurement
is performed in the usual way to an RF signal. In the conversion, bear in mind
that for every unit of optical attenuation (one dB), occurs two dBs of power loss
in
RF . As an example, every 3 dB of optical attenuation for each splitter are
equivalent to 6 dB of power loss for RF.