Tiernan TDR7, Manual

Page: 100 / 226

Chapter 4 88
Using a Remote Control Device Interface
QPSK Demodulator (QD) Commands
The QD command
allows you to configure the demodulator and to display receive signal
status information such as Eb/No, receive signal level, and carrier
offset. Entering the QD command displays the current configuration
of the demodulator.
QD Command List
First Level
Mnemonic Second Level
Mnemonic
Effected Function
AGC
Displays the power level of the received signal in dBm. For
optimum performance, the power level must be between
–85
dBm and –20dBm.
CR Viterbi code rate
1/2 Sets Viterbi code rate to 1/2
2/3 Sets Viterbi code rate to 2/3
3/4 Sets Viterbi code rate to 3/4
5/6 Sets Viterbi code rate to 5/6 (DVB default)
7/8 Sets Viterbi code rate to 7/8
DR Displays the current transport stream data rate.
#
Enter the data rate of the transport data stream as a value
between 2 and 48
bps. The DVB default is 8448000bps.
EBNO
Displays the Eb/No of the receive signal. Information on
minimum Eb/No levels for each of the Viterbi code rates is
detailed in
Chapter 6 of this manual.
LNB Low noise block downconverter power and polarization
HORZ
Sets the low noise block voltage to 12 so that the LNB sets
the receive signal polarization to horizontal.
VERT
Sets the low noise block voltage to 18 so that the LNB sets
the receive signal polarization to vertical. (DVB default)