Comtech EF Data CDM-Qx, Инструкция по установке и эксплуатации

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CDM-Qx Satellite Modem Revision 6
Front Panel Operation MN/CDMQx.IOM
as shown below, to include the calculated Receive RF frequency of the modem/BUC
combination:
As the Rx IF frequency is edited, the RF frequency will automatically be updated.
(Config
%
Rx
%
Acq) – DEMOD ACQUISITION RANGE
The value entered here determines the amount of frequency uncertainty the demodulator
will search over in order to find and lock to an incoming carrier.
The range varies from
±
1 kHz to
±
32 kHz for 70/140 IF,
±
1 kHz to
±
(symbol rate/2) up
to
±
200 kHz for L-Band. For symbol rates < 64 ksps, it will be ± (symbol rate/2). For
L-Band, Acquisition Range < 625 ksps =
±
32 kHz, ≥ 625 ksps =
±
200 kHz.
Edit the acquisition search range of the demodulator (the value entered here determines
the amount of frequency uncertainty the demodulator will search over in order to find and
lock to an incoming carrier). Edit the value by selecting the digit to be edited, using the
! " arrow keys. The value of the digit is then changed using the #$ arrow keys, then
pressing
ENTER
.
(Config
%
Rx
%
Descram) - DESCRAMBLER
Options are:
Default-On
The appropriate descrambler type is automatically selected.
IESS-315-On This only applies when Turbo is installed and has been selected as the FEC type.
Off No descrambling.
As before, the options are displayed all of the time, but the
◄ ►
arrow keys will force
the cursor to skip past an unavailable choice.
The default descrambler types are:
Viterbi, no framing:
ITU V.35 (Intelsat variant)
Viterbi, EDMAC frame: Comtech proprietary, frame synchronized
V RS or TCM/RS: Per IESS-308, frame synchronized
TPC: Comtech proprietary, frame synchronized
Descrambling: Default-On
IESS-315-On Off ( ◄ ► ENT)
Demod Acquisition Range:
+/- 32 kHz (
▲ ▼ ENT)
Rx IF Freq:1156.3456 MHz
RF=12156.3456 ( ◄ ► ▲ ▼ ENT)
IMPORTANT
5–25