R&S FSL Cable TV Measurements (Option K20)
1300.2519.12 2.93 E-11
Table 2–14: Digital TV service data for 64QAM_6900 modulation standard
Standard QAM J.83/A (DVB–C Europe)
Constellation 64QAM
Symbol rate 6.9 MSymbols/s
Roll–off factor of root raised cosine filter 0.15
Sideband position normal
First of all in the second step, we will copy the EXAMPLE BAVARIA channel table to a new channel
table EXAMPLE WIPFING. We do this, because we want to keep the pure frequency plan (as
EXAMPLE BAVARIA channel table), and create an additional channel table EXAMPLE WIPFING for
our measurements in Wipfing.
1. Press the previous key, to go back to the Channel Tables dialog box.
2. Focus the channel table EXAMPLE BAVARIA via the knob or cursor keys.
3. Press the Copy softkey to copy the EXAMPLE BAVARIA channel table.
4. The Channel Table dialog box is displayed (see Fig. 2-65).
5. In the field Name, enter EXAMPLE WIPFING as channel table name, with the keypad.
6. In the field Description, enter in the same way EXAMPLE FOR PARTICULAR CATV NETWORK.
7. To save the new channel table, press the Save Changes softkey. You will be prompted if any
errors are encounterd. In that case, please correct all errors. If you followed the steps above
everthing should be fine.
We will then create the analog modulation standard, which we will call PAL_BG_STEREO and which is
based on the information of Table 2–13: We will continue with the channel table EXAMPLE WIPFING
from above.
8. Press the Modulation Options softkey.
The appearing list of all exisiting modulation standards is empty right now.
9. In the Modulation Options submenu, press the New softkey.
The Modulation Standard Options dialog box appears (see for example Fig. 2-66).
10. Enter the parameters for the modulation standard:
In the field Name, enter PAL_BG_STEREO as modulation standard name with the keypad.
Select Analog TV as Signal Type from the list.
This is done, because PAL B/G is an analog TV standard.
Select B/G as TV Standard.
This means that the luminance information of the video signal is transmitted via an AM
modulated carrier according to the standard B/G.
Select FM 5.5 / FM 5.742 as Sound System from the list.
That means that there are two sound carriers present, one 5.5 MHz and the other 5.7421875
MHz above (for a normal sideband position) the vision carrier frequency.
Select General for the Group Delay from the list.
Select PAL for the Color System from the list.
The color information of the video signal is transmitted according to the PAL standard.
For the Bar Line, set Line to 17 and the Type to CCIR17.
That means, that a special test signal, the so called bar line, is transmitted in the horizontal line
17 of the TV signal.
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