- 6 -
- 6 -
2.5 Description
This head-end station is the basic unit of a modular system for the reception and
conversion of analog satellite broadcasts (radio and TV), digital satellite broad-
casts (radio and DVB TV =
D
igital
V
ideo
B
roadcasting), and terrestrial radio
and TV broadcasts. It is provided for the installation of medium-sized and large
broad-band cable systems.
This head-end station is designed exclusively for use with cassettes of the Stand-
ard marketing programme. You can find a list of the current Standard cassettes
at the website “
http://www.triax.com
”. The various expansion options for the
head-end station allow for the installation of a wide range of broadband cable
systems.
After connecting the head-end station to the mains voltage, all cassettes are
supplied with the required operating voltages by a switched-mode power sup-
ply unit via the plug-in connectors on the contact rail. The central control unit is
connected via I
2
C bus lines (SDA, SCL) to the cassettes. The passive input splitter
provides highest flexibility when selecting signals with horizontal or vertical po-
larization. The cassettes are connected to the outputs of the input splitters. The
input splitters can be operated from a remote voltage supply, that is, the LNBs
can be supplied with an operating voltage of +18 V and a current of max. 1 A
( I
max.
< 800 mA per input splitter). Each of the two inputs has nine outputs. All
RF output signals of the cassettes are unified in the RF output collector, and then
passed on to the RF »
OUTPUT
« socket of the head-end station. The RF output
level of about 80 dBµV depends on the cassettes fitted.
At the factory, the output level controls of the head-end station are set to maxi-
mum-output level for the cassettes. Please adjust the output level of the individual
cassettes with the associated level controls on the front panel of the head-end
station to the following values:
For analog TV broadcasts to about 70 to 80 dBµV.
For digital TV broadcasts (64 QAM) about 6 to 10 dB lower than for analog
TV broadcasts.
For FM radio broadcasts about 10 dB lower than for analog TV broadcasts.
The RS 232 interface of the control unit enables you to use a PC or a note-
book and the “
BE-Flash
” software to update the operating software of the
control unit. You can find the current operating software for the control unit,
the software “
BE-Flash
” and the current assembly instructions on the website
“
http://www.triax.com
”.
