GSS HDMC 1000 C, Руководство по сборке

Страница: 23 / 44

- 23 - HDMC 1000 C
—> Setting " burst "
The data packets of the user data are spaced out evenly in the trans-
port stream.
• Press the button.
—> The "Channel strip" – " LINE " menu is activated.
C
hannel striP
Herein select the channel strip for which the following settings should be done.
Bx 4
Line A <= LINE
=> Line B
• By pressing select channel strip " A " (" Line A ") or select channel strip " B "
(" Line B ") by pressing the button.
—> The "Channel / Frequency setting" – " OUTPUT " menu is activated.
C
hannel
/ f
requenCy set ting
In this menu, you can select the channel or frequen cy setting for the adjustment
of the RF output. The channel setting covers the range of channels S21…C69,
the frequency setting covers the range from 42.0 MHz to 860.0 MHz.
The QAM signal is normally transmitted with a bandwidth of 8 MHz. This
means that you can only use the channel centre frequency of the existing
channel grid in the range of channels S21…C69 (frequency grid 8 MHz).
Please note thereby that many receivers cannot receive the channel ranges
S21…S41 (306 … 466 MHz).
The CCIR channel grid is 7 MHz in the range of the lower frequency bands
(channels C2…S20). Therefore the frequency setting is used here. If one uses
the existing channel grid of 7 MHz in these channel ranges, this will result in
interference (overlapping) with the 8 MHz QAM signal packages, thus caus
-
ing transmission problems.
For programming in these channel ranges and in the frequency ranges below
them, we recommend starting with channel S21/306 MHz going back in
steps of 8 MHz (see frequency table on page 42), or reducing the bandwidth of
the QAM output signal by removing stations.