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HDMU 790 C
Switching the modulator on or off:
• Use the button to place the cursor under "on" resp. "off".
• Use the
buttons to switch each modulator on or off.
• Press the button.
—> The "Channel / Frequency" – "
FREQ
" submenu is activated.
C
hannel
/ f
requenCy
In this menu you can adjust the output channel (only at modulator A and C) or
the output frequency of the respective modulator.
—> The QAM signal is normally transmitted with a bandwidth of 8 MHz.
This means that you can only use the existing channel grid in the
range of channels C21…C69 (frequency grid 8 MHz).
The CCIR channel grid is 7 MHz in the range of the lower frequency
bands (channels C5 … C12, S2…S20). If 8 MHz QAM signal
packages are transmitted in these channel ranges, this will result in
interference (overlapping) and transmission problems.
For programming in these channel ranges and in the frequency rang-
es below them, we recommend starting with frequency 306 MHz
going back in steps of 8 MHz (see frequency table on page 40).
Please note thereby that many receivers cannot receive the channel
ranges S21 … S41 (306 … 466 MHz).
Channel setting (S21 … C69; only modulators "A" and "C"):
Bx 4A
C66
FREQ
785.14 MHz
FREQ
850.00 MHz
Bx 4C
C68
—>
The channel setting is only possible for modulators "A" and "C".
• Use buttons
to select the cursor position for channel setting.
• Use buttons
to adjust the desired channel.
—> The modulators "B" and "D" by default are fixed to a spacing of
+ 8 MHz to the modulators "A" and "C" (forced adjacent channel
setting). Only this spacing to the modulators "A" and "C" can be set
via the frequency setting.
