User Manual

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The distance of the thresholds from the optimal value is of ±20mV and ±30mV measured as monitor voltage.
The AGC changes the output power to bring the power from the amplifier inside the goal thresholds range.
When this goal is achieved, the AGC stops until the power goes outside the action thresholds range.
The AGC is stopped immediately (output power remains blocked to the value reached at the moment in
which the AGC stops) when one of the following conditions occurs:
z RF output is muted for an alarm condition or user setting;
z the AGC is chosen as external but the amplifier stage triggers an alarm;
z the ATSC TRANSMITTER output power is too low;
z the AGC has corrected the output power too much.
In order to simplify the understanding of the AGC behaviour, the status of the external AGC is written in the
Power menu (Ext AGC Status parameter). The possible statuses of the AGC are listed below.
z Disabled: external AGC is disabled.
z Idle: external AGC is stopped (for example, during the slow increase of the power immediately after
switching on the equipment).
z Low Set: external AGC is stopped because external power reading was too low when the nominal output
power has been chosen.
z Alarm: external AGC is stopped because an alarm signal from the power amplifier stage is active.
z Locked: the transmitter output power has reached the desired level.
z Max/Min: external AGC is stopped because the power correction is too high.
z Pull Up/Down: external AGC is moving the power level up or down.
Warning! When changing from AUTO to MANUAL power control mode, the external AGC will be disabled.