Comtech EF Data KST-12025 - Manual (Page 90)

Theory of Operation KST-12025 Ku-Band Satellite Terminal
5–4 Rev. 1
5.1.2.1 Remote Interface Specification
Refer to Appendix A.
5.1.3 Terminal Default Conditions
On initial power-up, the unit will default to the following parameters.
Parameter Default
Baud Rate [9600]
Parity [Even]
Device Address [1]
U/C Gain [10.0]
D/C Gain [0.0]
RF Output [OFF]
U/C Frequency [Low end of range]
D/C Frequency [Low end of range]
5.1.4 Theory of Operation
Refer to Figure 5-3 for a functional block diagram of the M&C.
The M&C PCB performs the following operations:
•
Receives the desired frequency from either the remote EIA-232-C/485 or local
keypad, and after converting it to a synthesizer setting, stores it to the applicable
synthesizer output latch.
•
Reads the thermistors located in the up converter, down converter, and high-
power amplifier, and converts them to temperatures for display.
•
Reads the characterization EEPROMs in the up converter, down converter, and
high-power amplifier, and calculates an Automatic Gain Control (AGC) voltage
based on frequency and temperature to linearize the respective module.
•
Turns the fan on or off, depending on the temperature.
•
Receives fault inputs from all modules, and presents them to the remote EIA-
232-C/485 and the optional local keypad display.
•
Performs an initial current sense on the LNA, and stores the reading in
EEPROM. Subsequent current sense readings are taken and compared to the
initial reading to determine a fault.