Kathrein UFO 386/TP Manual De Instrucciones página 22

7. Selecting the modulation signal for the QAM modulator
Input 1568
27,500 MS/s
Output S21
6,875 MS/s
Main menu
The selection of the modulation signal for the QAM modulator is carried out in the submenu of the QAM ranges.
Access the submenu with the "+" or "–" key and make the desired setting.
Possible settings are :
● "SAT-Sig"
Standard operation, the Sat input signal is converted, no output signal during interruption of
the input signal
● "SAT-PRBS"
Standard operation, the Sat input signal is converted, output signal switches during interruption
of the input signal to PRBS-23 (output spectrum remains the same).
● "PRBS"
Test signal PRBS-23. Independent from input signal. Standard operation is not possible.
● "CW-Mode"
Test signal for levelling with simple measuring instruments. Standard operation is not possible.
If the CW signal is switched on (only selectable in twin A), a sinusoidal carrier with 85 dBµV is generated
on both channel units (both twin A and twin B).
In the "PRBS" operating mode, the output symbol rate (e.g. 6.875 MS/s) can be set (see selection of the output symbol
rate in operation mode PRBS and Stuffing with and without programme filter).
Output S21
6,875 MS/s
Main menu for PRBS
In the "Sat-PRBS" operation mode, the channel unit automatically transmits PRBS if the unit cannot lock on to the set Sat
signal. In this case, the previously set output symbol rate for "PRBS" or "Stuffing" is valid. If the output signal can be
modulated again, the channel unit switches back to transmodulation.
If the output symbol rate is to be set, it is necessary to choose the operation mode "PRBS" temporarily or to switch
to "Stuffing". Setting to "Sat-PRBS" is not possible.
It is recommendable to set the output symbol rate to the same value as the automatically determined symbol rate for the
set transponder so that the output spectrum remains the same when switching over to PRBS.
While the channel unit transmits the PRBS replacement signal in the SAT-PRBS operating mode, the following will be
displayed on the control unit (the code rate is not displayed because the input has not locked in).
6
MHz
3/4
306,00 MHz
64 QAM
PRBS
TP
306,00 MHz
64 QAM
*** UFO 386/TP
Modulation
Spectrum
< Return:
Submenu QAM stages
*** UFO 386/TP
Modulation
Spectrum
< Return:
Submenu QAM stages, PRBS setting
***
SAT-Sig
normal
Submenu >
***
PRBS
normal
Submenu >