Axcera INNOVATOR, Инструкция по эксплуатации

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UHF Analog Driver/Transmitter/ Chapter 2, System Description,
Translator Maintenance & Remote Control Connections
LX Series, Rev. 3 2-6
module RF power level with the desired
level and uses the IF Power Control PWM
line to correct for errors.
In digital systems, a digital level control
(DLC) voltage is generated on the IF
Processor module and sent to an
external digital modulator (DT1B/C). RF
power control is implemented by
changing the DLC voltage provided to
the external digital modulator. The 'RF
High' potentiometer sets the upper
adjusted range of RF control circuit
output to 120%.
The IF Processor module provides a
reference ALC voltage to the system's
Upconverter. When the ALC voltage
decreases, the Upconverter
automatically lowers the system output
power through the AGC circuits.
The IF Processor module has a front
panel switch to select Auto or Manual
ALC. When Manual ALC is selected, the
reference ALC voltage is set by a front
panel potentiometer. In this condition, the RF power level control circuit is
removed from use. When the ALC select
switch is changed to Auto, the RF power
level control circuit will start at low
power and increase the RF output until
the desired output power is attained.
The IF Processor module Modulation
Present signal is monitored. If the
modulation level is too low or non-
existent, a Modulation Present Fault is
reported to the Control Monitoring
board. When the controller detects this
fault, it can be set to Automatically Mute
the transmitter or in Manual mode the
transmitter will continue to operate at
25% output.
The IF Processor module Input Signal
level is monitored. If the signal level is
too low or non-existent, an Input Fault
is reported on the Control Monitoring
board. When the IF Processor board
detects an Input Signal Fault it
automatically Mutes the transmitter.
The system controller does not Mute on
an IF Processor Input Fault.
Table 2-10. IF Processor Front Panel Switch
SWITCH FUNCTION
MAN/AUTO ALC
When Manual ALC is selected, the reference ALC voltage is set
by the ALC Gain front panel potentiometer.
When Auto ALC is selected, the IF level control circuit will
automatically increase the IF output until the desired output
power is attained.
Table 2-11. IF Processor Front Panel Status Indicators
LED FUNCTION
INPUT FAULT (Red)
When lit it indicates that there is a loss of the IF Input signal to the
IF Processor. Transmitter can be set to Mute on an IF Input Fault.
ALC Fault (Red)
When lit it indicates that the required gain to produce the desired
output power level has exceeded the operational range of the ALC
circuit. The LED will also be lit when ALC is in Manual.
MUTE (Red)
When lit it indicates that the IF input signal is cut back but the
enable to the Power Supply is present and the +32 VDC remains on.