Televes DTT Manual De Instrucciones página 31

User manual
of the addresses are repeated on this bus.
The address is a parameter that is saved
every time it is modified.
2.- Preamplifier powering. The processor
disposes of 12V that passes through the
input connector to power a preamplifier for
those cases in which the input level is less
than the minimum required.
To select this powering, the user must use
the & buttons.
The programmer's display will read 12ON if
the power is in the input connector and
12OF when it is not:
3.- By pressing the button again, the user
gains access to the menu that deals with the
slope variation.
This lets you adjust the flatness of the digital
channel by up to ± 3 dB. If the slope values
are positive, then this indicates that the pro-
cessor's response curve (with the highest
frequency) is such that the top part (with the
highest frequency) of the channel is attenua-
ted with regard to the lower part, while
negative values indicate that the amplitude
of the lower part is lower.
The format of the display for a selected
slope of - 2dB would be:
By pressing the & buttons, the user
can select the desired slope in steps of 1
dB.
4.- Press the key again to select the next
menu for the input frequency offset. In this
mode also the A LED will be ON.
Pressing the & keys an offset value between
+3, +2, +1, 0, -1, -2, -3 can be selected.
Each one represents a frequecy shifting
according with the following tables:
Ref 5870
OF-3 -3 x 166 KHz
OF-2 -2 x 166 KHz
OF-1 -166 KHz
OF-0 Nominal Frequency
OF+1 +166 KHz
OF+2 +2 x 166 KHz
OF+3 +3 x 166 KHz
31
DTT Channel Processor
Ref 5871
OF-3 - 3 x125 KHz
OF-2 -2 x 125 KHz
OF-1 -125 KHz
OF-0 Nominal frequency
OF+1 +125 KHz
OF+2 +2 x 125 KHz
OF+3 +3 x 125 KHz
For an offset value -1, the display will show
the following:
Record data as done in the normal menu.
5.- Press the key again to select the out-
put frequency offset. In this mode the "C"
LED will be ON.
Follow the previously explained procedure
for selecting, changing and recording the
data.