System Description Chapter 2

10-kW UHF Transmitter with Chapter 2, System Description
Feedforward Driver
840A, Rev. 0 2-12
STATUS INDICATOR FUNCTION
step-start and high-voltage contactors.
When the main AC and HV circuit breakers
are turned on, 208/240 VAC is applied to
the transformer of the high-voltage power
supply.
Screen (DS12)
Indicates that the high voltage (plate
voltage) is on and the Screen On command
(Enable) has been given to the isolation
relay (A7) mounted in the screen power
supply assembly. The relay energizes and,
when the screen circuit breaker is switched
on, applies 220 VAC through the Sola 60 Hz
regulator to the transformer (T1) that is
part of the screen power supply.
RF Request (DS13)
Indicates that the tube has all of the
voltages applied and that the RF On
command (Enable) has been given to
enable the exciter/driver assembly that
applies the RF drive to the 10-kW amplifier
Table 2-13. 10-kW Amplifier Assembly Operating Status Indicators
STATUS INDICATOR FUNCTION
Blower (DS16)
Indicates that the blower is on. The
quantity of air flow through the exhaust
stack is measured by the air pressure
sensor.
Filament (DS17)
Indicates that the above step is complete
and that the filament voltage is on. This is
indicated when the filament voltage on
sense at J12-11 of the control logic board is
low.
Bias (DS18)
Indicates that the above steps are complete
and the bias voltage is on. This is indicated
when the bias on sense at J13-2 of the
control logic board is low.
High Voltage (DS19)
Indicates that the above steps are complete
and the high voltage is on. This is indicated
when the high voltage on sense at J13-8 of
the control logic board is low.
Screen (DS20)
Indicates that the above steps are complete
and the screen voltage is on. This is
indicated when the screen voltage on sense
at J13-14 of the control logic board is low.
RF Present (DS21)
Indicates that the above steps are complete
and that there is an RF output from the
transmitter. This is indicated when there is
a forward power sample fed to (J15 - 7 and
6) of the transmitter control board.