Radyne DMDVB20 LBST, Installation And Operation Manual

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DMDVB20 LBST Satellite Modem Appendix C
TM138 – Rev. 1.0
C-
1
Carrier Control
C
C.0 States
The transmitter will turn off the carrier output automatically when the modem determines there is
a major alarm. This is done to prevent the carrier from outputting an unknown spectrum and
possibly disturbing adjacent carriers. This automatic drop of the carrier can be overridden by
masking the alarm that is causing the fault. This will keep the modulator output spectrum
transmitting, even when the fault occurs. The following Carrier Control states are available:
Carrier OFF
Carrier ON
Carrier AUTO
Carrier VSAT
Carrier RTS
C.1 Carrier Off
Modulator output is disabled.
C.2 Carrier On
Modulator output is turned off before reprogramming modulator functions that may alter the
output spectrum through the front panel, and the user is required to enter “Yes” to re-enable
output after the change. When using the terminal, the modulator is turned off while re-
programming modulator functions that may alter the output spectrum, and the user is required to
manually turn on the output after the reprogramming.
C.3 Carrier Auto
Modulator output is turned off before reprogramming modulator functions that may alter the
output spectrum through the front panel, but the output is automatically turned on after the
change. When using the terminal, the modulator is turned off while re-programming modulator
functions that may alter the output spectrum, and but the output is automatically turned on after
the change.
C.4 Carrier VSat
Modulator output is turned off before reprogramming modulator functions that may alter the
output spectrum through the front panel, and the user is required to enter “Yes” to re-enable
output after the change. When using the terminal, the modulator is turned off while re-
programming modulator functions that may alter the output spectrum, and the user is required to
manually turn on the output after the reprogramming (same as “Carrier On”). Additionally “VSat”
mode disables the modulators output when the modems demodulator does not have signal lock.
When signal lock returns to the demodulator, the modulator turns the carrier back on.