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System functions
Digital terrestrial and satellite signals are fed to the optical transmitter (OSC 100) which
converts the electrical signals into optical signals, thus allowing distribution over long
paths using a fibre-optic infrastructure.
Suitable splitters (OVC xxx) and taps (OAC xxxx) are available for distribution of the opti-
cal output signal.
Notes on planning the fibre optic system
When designing a fibre optic system, it is important to consider the optical input levels to
the receiver (OEC 40 mini or OEC 44 mini). To ensure that the system fulfils the required
parameters, appropriate attenuation must be calculated at each point. The optical output
power from the transmitter (OSC 100) is typ7 dBm. The input level of the optical
receiver (OEC 40 mini and OEC 44 mini) lies between -8 dBm and -14 dBm. This results in
an allowable attenuation of the optical network of 15 to 21 dB.
The catalogue contains a whole range of optical attenuators and taps/splitters which have
different attenuation values and enable the optimisation of the system. Please use the
Kathrein CLIKulator to plan and adjust your optical distribution network
(http://clikulator.com/kathrein).
• If directly connected without splitters or taps, attenuators must be used
between the OSC 100 and OEC 40 mini/OEC 44 mini. To avoid over-
load, the input power on the receiver must not surpass -8 dB.
• If the quality of an input signal is not optimal or if a multi-carrier signal
must be distributed over a large coaxial distribution network, the optical
budget should be decreased.
• The level difference of a satellite transponder polarity (VL/VH/HL/HH)
should not exceed 4 dB. If the transponders have a gain slope on the
inputs of the OSC 100 and the level is high enough, you can use the
passive equalizer ERZ 60 in certain circumstances to adjust the level
(use one ERZ 60 for each satellite polarisation). If a long coaxial cable
is used between the LNB and the OSC 100, you can adjust the level
and the gain slope (for each satellite polarisation) with the VWS 2500.
If several transmitters (OSC 100) are cascaded, a VWS 2500 satel-
lite distribution amplifier must be connected between the third and the
fourth OSC 100 and also between the fifth and sixth in the cascade. The
maximum quantity is seven in the OSC 100 cascade.