Comtech EF Data OM20 - Manual (Page 105)

OM20 Universal Outdoor Modem Web Browser/Remote Protocol
MN-OM20– Revision 5 6–31
Downlink Frequency (MHz): Displays the input frequency into the LNB from the satellite,
also referred known as Satellite downlink frequency. The user
must enter the LNB LO and OSC SIDEBAND of the LNB
before using this menu. The DOWNLINK FREQUENCY is a
calculated measurement of both the LNB LO and OSC SIDE
BAND. Once the menus are entered correctly, the user can
control the downlink Frequency from this menu.
Spectrum:
{Normal, Inverted}
Allows the user to invert the direction of rotation for PSK
Demodulation. Normal meets IESS Specification.
Spectral inversion may be required if the LNB LO is higher in frequency
than the LNB input frequency from the satellite. When LNB LO is higher in
frequency than the LNB input frequency, this creates a spectral inversion
and the IF Spectrum must be inverted to compensate.
Demodulation: {QPSK, BPSK, OQPSK, 8PSK, 16QAM}
Allows the user to select the demodulation type.
Spectral Mask:
{Intelsat 0.35, DVB 0.35, DVB 0.25}
Allows the user to invert the direction of rotation for PSK
Modulation. Normal meets the IESS Specification.
Sweep Range (kHz): {±0 to 255 kHz}
Allows the user to set the acquisition range for the demodulator
Sweep Delay (sec): {0.0 – 900.0 sec}
Allows the user to set the reacquisition delay time in 1/10
th
second increments.
Reacquisition Range (Hz): {0 – 32000 Hz}
Allows the user to set the reacquisition sweep in 1 Hz
increments.
Adj Carrier Pwr: {Normal, Suppressed}
Allows the user to indicate adjacent carrier as Normal or
Suppressed (High Power). Unit will increase or decrease post
dissemination gain appropriately.
Fast Acquisition: {DISABLED, ENABLED}
Allows the user to disable or enable the Rx fast acquisition
capability.