User manual
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Superior Broadcast
ATVCA Amplifier User Manual
Superior Boadcast ATVCA Amplier
The ON LEDs on both modules will turn on and the forced cooling fans will start
running. The LCD shows the introductory screenful and then switches to a screenful
that indicates the forward and reected power values.
Turn on the exciter (at lowest power) and wait for its complete bootstrap routine.
Once ready, increase RF power output gradually and check on amplier’s LCD
display. Increase the exciter’s power until the amplier’s RF output power attains
the planned value.
All machine’s operating parameters may be checked remotely via a remote
hardware/software control system.
As a rule, the amplier operates automatically. If any alarm conditions occur, they
will be managed automatically by the protection system and notied to the user
by means of LEDs on the panel and messages on the display.
6.3 On Air
The amplier always must be connected to antenna (or dummy load), also when in
absence of RF excitation. Above all, risky occurence comes up when the amplier is
put in ‘ON’ state putting DC power supply available to RF units. When the amplier
is connected to an RF output lter, as mostly, and its output can’t nd a receiving
outlet, self oscillations in RF eld may arise so strongly that permanent damage
in the RF output lter may occur.
The amplier must work at a precise level of RF Output power, admitted tollerance
is within +/- 0.5 dB. The amplier and its own exciter are mutually ne tuned in
order to comply the RF signal quality requirements of Communications Supervisory
Authority. These adjustment, linear and non-linear pre-correction for understanding,
are greatly dependent by RF output power, so this output level cannot be freely
modied after having reached the satisfactory result.
It would be better that the amplier do not work bordering its limit of any protection.
If an environment’s parameter reaches the protection threshold, the amplier is
switch off. The right work load for the amplier is a careful user’s choice, although
amplier is ever self-protecting, some available operating margin can compensate
environment’s parameters uctuation, avoiding invalid transmission times.
The antenna is the natural outlet of RF power supplied by the amplier. Working
stability of the antenna is prominent in order to warrant the quality of transmitted RF
signal and for equipment’s reliability. Amplier can manage antenna’s
anomalies
but, its duty is to defend itself only. Nothing is set in action by the amplier in order
to remedy about integrity of RF transmitted signal, so it is a customer’s liability to
warrant antenna’s working stability or, otherwise, to provide an arrangement that
deals with this consequence.
ATVCA
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User Manual
Rev. 1.0 - 22/11/10