Comtech EF Data CDM-710 Installation And Operation Manual page 132

CDM-710/L Broadcast Satellite Modem
Front Panel Operation
The range varies from ±001 kHz to ±100 kHz. To edit the demodulator acquisition
search range value: Use the   arrow keys to select the digit, and then use the
 arrow keys to change that digit. Press ENTER.
(Config:) Rx:  Dem 
The Rx Alpha Rolloff (α) setting dictates how fast the spectral edges of the
carrier are attenuated beyond the 3 dB bandwidth. With 20% rolloff the edge
falls off more quickly than with 25% and 35%.
The default Rx Alpha Rolloff setting is 20%. Whenever the Mode is changed, (α)
reverts to 20%.
Use the   arrow keys to otherwise select 25% or 35%. Press ENTER.
(Config:) Rx:  Dem  Eq
The adaptive equalizer helps correct for linear distortion in the rest of the link.
Linear distortion includes amplitude and phase that would occur due to
imperfect filtering effects, but it does not include distortion due to non linear
amplifiers.
Use the   arrow keys to select operation as Off or On. Press ENTER.
(Config:) Rx:  Dem IQ-TP
This selection determines whether the IQ test point, located on the rear panel 'J2
| Alarms' connector, samples the IQ signal before or after the Adaptive
Equalizer. "J2-11" and "J2-3" refer to the pins on the connector that an
oscilloscope connects to, to monitor I and Q.
α
Rx (α) Rolloff %: 20 25
35
Rx Adaptive Equalizer:
Off On
Rx IQ TPs (J2-11,J2-3):
Pre-EQ Post-EQ
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MN/CDM710.IOM
Revision 12
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