Operation Manual Part 3

Digital Liquid Cooled UHF
TV Equipment
Operating modes and Control modes
9946 V1
45321648.01 104 A E
preliminary
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Numéro / Number Doc. Rev. Lan
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16/06/2006
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Information contained is this document is confidential, is THOMSON property and cannot be disclosed in whatever form without prior written authorization of THOMSON.
4. Operating modes and Control modes
4.1. SIRIUS initialisation
♦ When the SIRIUS is commissioned it must receive initialisation commands from the transmitter
CPU:
Some SIRIUS operational parameters which are in the CPU memory are transferred to the SIRIUS
by a command from the PCL (in maintenance mode).
Afterwards, the operator can change some of these parameters using the PCL.
4.2. Transmitter operating modes
The transmitter has the following modes of operation:
♦ Installation mode:
The transmitter assumes this mode when mains is first switched on or when the CPU card is
replaced. It consists of an initialisation procedure for the CPU card.
In this mode the control system sets the transmitter operational parameters and status conditions
to the default values; these values can be changed by the operator using the PCL.
The principal facilities available in this mode are as follows:
• polling,
• making entries in the log book,
• display of installation window.
The following important facilities are not available:
• processing of faults,
• command control system.
♦ Normal mode:
In this mode all operational facilities are available. Selecting maintenance commands on the exciter
cards or adjusting/changing parameters on the PCL (alarm threshold, power reduction, etc.) are not
available.
♦ Maintenance mode:
In this mode the fault analysis and processing system is not available. Operations and commands
which are not available in normal mode can be carried out by the operator.
4.3. On-air mode
This mode can be activated automatically or manually as follows:
♦ when automatic switch to air mode has been selected:
• the transmitter can only go on-air if an input signal is present,
• if no input signal is present the transmitter will be switched off air by removing the amplifier
power supply feed.