GSS HDM 660 T, Руководство по сборке

Страница: 17 / 42

- 17 - HDM 660 T
—> If a channel strip is selected whose modulator is switched off, in-
stead of the frequency or the channel " – – – " is displayed.
Bx 1A
– – – COFDM-TPS
V 12
—> Programming the channel strips " A " and " B " is identical without a
CA module. If a CA module is used mind the supplementary pro-
gramming procedure described on page 35.
• Press the button.
—> The "Channel / Frequency setting" – " OUTPUT " menu is activated.
C
hannel
/ f
requenCy set ting
In this menu, you can choose whether you require the channel or frequency
setting for the adjustment of the HF output. The channel setting covers the
range of channels C5 … C12 und C21 … C69, the frequency setting covers
the range from 42.0 MHz to 860.0 MHz.
Bx 1A
Freq. OUTPUT
—>
The COFDM signal is normally transmitted with a bandwidth of 8
MHz. This means that you can only use the channel centre frequen-
cy of 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). If
8 MHz COFDM 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
ranges 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).