Operation instructions | MK 8-0x | MK 16-0x | MK 8-2x | MK 8-0xN | MK 12-0xN
42
2022-07-27 | Technical improvements, changes in design, printing- and other errors reserved.
4.3.3.
MK 8-2x (DVB-T2)
Configuration of the modulators
Select a modulator from MODULATOR 1 to MODULATOR 3 on the left.
Make the required settings.
Click SAVE for each modulator.
Only then the changes will be saved,
otherwise the changes will be lost.
Parameters:
Common Output level
The
Common Output Level
option include a general attenuation of
all
modulator outputs. The highest output level is reached with a setting of 20 dB,
the lowest level with a setting of 0 dB.
Norm
In this selection field, you can set the norm for the output channel spacing.
Note: Changing the norm works now according to following rules:
•
CCIR ->Australia : all modulators forced to 7MHz
•
Australia ->CCIR : all modulators forced to 8MHz, however with following
exception: low channels S2-S20 are 7MHz only, so those remain in 7MHz
Output Channel
Each of the modulators can be set to any output channel.
No output channel
may be selected more than once!
DVB-T2 Constallation
The modulation can be adjusted to the following methods:
•
QPSK (2 Bit/symbol) – small data rate – very robust signal.
•
QAM 16 (4 Bit/symbol) - low data rate.
•
QAM 64 (6 Bit/symbol) - middle data rate.
•
QAM 256 (8 Bit/symbol) - high data rate.
FEC Coderate
Thanks to the error correction, errors resulting from high-disturbed transmission
routes can be balanced by restoring data. The data required to restore the
signal are included in the transmitted FEC bits.
Changing the FEC factor modifies the part of the FEC data in relation to the
application data (1/2, 3/5, 2/3, 3/4, 4/5, 5/6). A higher part of FEC data means
an higher transmission redundancy. But this reduces the bandwidth for the
useful data too.
•
FEC 1/2 - small data rate - strong protection against errors.
•
FEC 5/6 - high data rate - weak protection against errors.
Select a
modulator
