emitor Satlook Digital NIT, Руководство пользователя

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When performing Digital installations, please notice:
•
The constellationdiagramme is like ”a shower of hail”. No signal will spread
out the noise over the window. The better signal, the more concentrated and
focused ”hailstorms” in the windows.
•
SNR. The signal/noise ratio should be as high as possible. A good signal
should have at least 8.0 dB S/N-ratio.
•
BER. The Bit Error Rate should be as low as possible.
As the values are really small, on the other side of zero (presented as
something raised to minus something), they should be as high as possible.
A BER at 5.00 –05 is therefore better than 9.00 –04.
A BER at 4.00 –05 is therefore better than 5.00 –05.
It can be said, in general, that a signal should be at least x.xx –04 to be
accepted.
3.2.2. Other functions in digital mode
1.
Automatically search for the next digital transponder higher
in frequency. Searching is displayed at the bottom of the
monitor.
2. Search –
Automatically search for the next digital transponder lower
in frequency. Searching is displayed at the bottom of the
monitor
3. Memory
For storing digital transponders (digital channels -
frequencies).
- Tune in the ”right” frequency before entering this function
(ex. 1650 MHz).
- Enter the Memory function (button nr 3) and push Save
(button nr 1). The instrumentet asks: -”SAVE. ARE YOU
SURE ?”
- Check that the Memoryposition is the right one (displayed
at the right bottom on the monitor). If not, chose a new one
with the knob (0-99). Free positions are named: Pos free
- After selecting a position, push button nr 1 (YES).
Notice that even the preselected 13V/18V, 22 kHz on/off
will be memorized.
- Load a memory-position by pushing the control-button.
“Memory” will appear on top of the LCD and a memory-
position will be shown in the bottom of the LCD-display.
Step between the stored memory-positions with the knob.
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