Self-Monitoring Local Modem Aupc Control - Comtech EF Data SDM-300A Installation And Operation Manual

Options
5. Caution shall be observed when setting the target E
A.1.4.1.1

Self-Monitoring Local Modem AUPC Control

Note: This feature is available with or without the overhead PCB installed. Self-
monitoring AUPC is not used when the ASYNC/AUPC is selected as the Modem Type,
because the ASYNC/AUPC feature uses the overhead channel to control the modem's
output power.
The operator can allow the modulator to control its own TX power when the earth station
is in the same satellite footprint. The operator should tune the demodulator to receive its
own signal, similar to a satellite loop.
Note: This option can be used for half-duplex operation and for one signal transmitting to
many sites. For full-duplex operation, use a separate demodulator.
This option is located in the Utility/Modem Type/Local Modem AUPC menu. Proceed as
follows:
1. Locate and enable the option.
2. Set all configuration parameters.
Notes:
1. Comtech EFData does not recommend increasing the power to the satellite
2. Be careful not to set carrier output to the high-side when there is a loss of carrier
3. Do not use the distant end RX signal to compensate for local rain fade unless
4. Changes in local weather will attribute to cause level unbalancing in the TX
A–22
Notes:
1. Modem B will not make changes to modem A if the E
0.5 dB of the target noise.
2. Modem B will not control modem A transmitting output level if the
target noise for modem B is set within 15.5 to 16.0 dB and the receive
signal to the modem is sufficient that the receive noise is 16 dB or better.
3. Modem A will be transmitting at the maximum output if the local carrier
loss action is set to maximum.
maximum limit is established at 16.0 dB.
Notes:
1. Local carrier loss always takes priority over remote carrier loss.
2. The RX AUPC link is dead when the carrier is lost.
without consulting with the satellite controller.
due to severe weather.
allowances are made for a narrow window for TX level changes.
signal. The TX signal is attenuated due to heavy, dense, or cloud conditions.
SDM-300A Satellite Modem
/N is within
b 0
/N above 15.5 dB, the
b 0
Rev. 4