Codan Cascade Operation Manual page 37

37
Cascade Power Amplifier
Digital Control Board
The function of the digital control board is to provide all the management and control functions for the
PA, generate the supply voltages for the 40dBm stage and manage the communication with the rest
of the CASCADE subsystem.
40dBm Stage
The 40dBm stage takes the input signal and amplifies it to the level needed for the 53dBm stage
to further amplify it to the required power setting. This stage also controls the attenuators in the
amplification and feedback paths for the proper operation of the Cartesian loop in conjunction with the
digital control board.
53dBm stage
This stage does the final amplification of the signal and also contains the directional couplers and
associated circuitry for the monitoring of the output VSWR and for the sampled output feedback
signal. An harmonic filter is also included in this board.
Isolator
The isolator is integrated into the PA to provide additional protection against bad VSWR conditions.
Alarms and Status
Six LEDs on the front of the PA provide the basic information about the power amplifier status and
potential fault conditions. These LEDs include DC power, alarm and transmit status indicators; and
low power, high VSWR and over-temperature fault condition indicators.
Operation
The PA can only be operated as a module or as modules in the CASCADE subsystem. Standalone
operation is not the purpose of this CASCADE module.
Cascade System Modules Operation Guide
OG-CASC-SYS-MOD-1-0-0P