9 / 16
To ensure that the signals are transmitted through the
fi
bre optic cables, the RF signals must
meet the following
requirements:
TV (DTT/CATV)
→
DVB-T, Cable TV
To ensure that the digital television signals are transmitted and received, the digital signals
to the transmitter should be set to the same high level, especially when multiple digital chan-
nels are transmitted.
As a guide, the input signals should meet the following requirements:
1. With QAM64 a maximum of 40 TV channels can be transmitted, with QAM256 a maxi-
mum of 20 TV channels. With limitations on signal quality, up to 25 QAM256 TV channels
can be transmitted. Wherever possible a TV channel grid in the lower frequency range
should be preferred.
2. Total input power: -19 dBm (90 dB
μ
V)
3. Depending on the number of digital TV channels, the following levels must be met at the
optical transmitter‘s (OSC 100) TV input:
All levels are stated per digital TV channel
• 40 TV channels with a maximum of 74 dB
μ
V
• 20 TV channels with a maximum of 77 dB
μ
V
• 16 TV channels with a maximum of 78 dB
μ
V
• 10 TV channels with a maximum of 80 dB
μ
V
• 8 TV channels with a maximum of 81 dB
μ
V
The minimum input level (per digital channel) should be at least 74 dB
μ
V.
If the quality of the TV input signal is not optimal or when the digital TV channels cannot be
equally levelled, the system should be adapted so that the optical attenuation of less than 21
dB is reached to ensure correct signal reception at the outlet (especially when many digital
channels are transmitted).
FM and DAB+
FM and DAB+ signal level should be at least 10 dB lower than the digital TV signals.
SAT
1. Input level:
At OSC 100 there must be a level of 69 and 86 dB
μ
V per transponder, so that the AGC
functions properly.
2. Differing levels within a satellite level: The level difference of a satellite transponder level
(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, in certain circumstances you can
Input level of the optical transmitter OSC 100
For cleaning purposes please use the optical cleaning set ORS 1 or the optical cleaning tool
ORW 1.
