Adtec RD-71 User Manual page 21

Symbol The number of symbols transmitted per second
Rate in Msym/s. The amount of data per symbol is
dependant upon the modulation type, e.g. QPSK,
8PSK, etc.
Acquisition Acquisition Range is defined as the range of
Range frequencies that the tuner will scan in order to
achieve carrier synchronization. Allows the
operator to select the range of frequencies that
the RF tuner will sweep through to acquire the
carrier. e.g. If the desired carrier is at 1.080GHz
and the Acquisition Range is set to 5MHz, the RF
tuner will sweep through 1.080GHz ± 2.5MHz to
acquire the carrier.
Roll-off The rolloff selection will determine the shape of
the input filter. The occupied bandwidth of the
modulated signal is the symbol rate multiplied
by (1+α) where alpha (α) is the rolloff factor
(%). By using a lower alpha, carriers can be
spaced closer together on a given transponder
or an increased symbol rate can be realized for a
given bandwidth.
ISI Control ISI Control configures the receiver for
Multistream Mode (Enabled) or Singlestream
Mode (Disabled, Default). If the receiver is
operating in Multistream Mode, an ISI value
must be entered.
ISI Multistream ISI (input stream identifier) is
required for multistream applications. If
Multistream Mode is enabled, BBHeaders
containing this value will be demodulated and
output to the receiver.
LNB State Enables or disables the LNB control
LNB Polarity This control is primarily used in "Universal" LNB
applications. The LNB Polarity control allows for
LNB polarization selection; the 13VDC source will
select the Vertical polarity and the 18VDC source
will select the horizontal polarity. For typical "C"
and "Ku" band applications, the 18 VDC option is
recommended.
LNB Tone This control is used only for Universal LNB
applications. A universal LNB can route the high
or low band from either polarity to the IRD. The
high band is selected by enabling the 22 kHz
tone and the low band is selected when the 0 Hz
tone is enabled.
16QAM_3/4
16QAM_7/8
8PSK_2/3
8PSK_5/6
8PSK_8/9
maximum value is determined by
feature key.
0 - 7.5MHz
AUTO
5%
10%
15%
20%
25%
35%
SINGLESTREAM
MULTISTREAM
0 - 255
OFF
ON
OFF
H(18V)
V(13V)
0KHz
22KHz
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