AP01 HD rev.09 UK
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CFO:
(Center Frequency Offset) it indicates the difference between the set frequency
(tuning) and the actual frequency of the carrier. It is an interesting parameter which
provides information about possible frequency drifts of the local oscillator of "LNB".
PWR
index:
it is followed by writing
OK
, or
HIGH
, or
LOW
when the level of input signal
is respectively correct, or too high, or too low.
The PWR index indicates whether the tuner’s input signal has a proper level to be decoded
and digitally measured (remember that it depends both on the attenuation set on the field
strength meter and on the signal’s available input level).
MER:
(Modulation Error Ratio) qualitative modulation value of the digital channel expressed
in dB. The higher the value is, the better the signal quality is. This measure is valid only
when the carrier is locked.
PLEASE NOTE:
for this measure, all causes of alteration of the theoretical modulation, such
as distortions and interference, are considered as noise
.
NM:
(Noise Margin) it indicates the value of reception margin, expressed in dB. The higher
the value is, the bigger the reception margin is.
RU:
quantity of uncorrected errors (from 0 to 65535), followed by the time span in which
errors have been counted. The timer, as well as error indication, is reset when the QPSK
signal is not locked.
CH BER:
it indicates errors present in the channel before corrections. It is the most
important index to estimate the signal quality in the installation.
It is instantaneously measurable with all signals (from very strong to weak). It is very
sensitive to environment and weather conditions (temperature, humidity, cloudiness,
efficiency of cable, amplifiers and all components of a reception-distribution installation).
Moreover, it enables to optimize the satellite-dish pointing.
pV BER (BCHBER on DVB-S2 mode):
it indicates errors present after respective
corrections of VITERBI stage or LDPC stage.
7.2.1.
USE OF MODULE
Set the frequency of digital channel, the voltage of LNB, the 22 kHz tone. It can be useful to
visually check whether there is digital signal, passing to spectrum-analyzer mode. Press the
DIGI
key to activate the module.
In order to make the module work properly, the level indicated by “PWR index” must be
“OK”. If it is necessary, use the attenuator.
Please note
: use the lowest possible attenuation compatibly with “OK” indication.
To set MODE and SYMBOL RATE parameters, proceed as follows:
1.
press the
MENU
key, turn the
SHAFT ENCODER
to select PARAMETERS;
2.
press the
ENTER
key, the cursor appears on the screen;
3.
turn the shaft encoder to move the cursor to MODE and press
ENTER
;
4.
turning the shaft encoder, select the DVB-S or DVB-S2 mode;
5.
press
ENTER
again to confirm selection.
To set the "
SYMBOL RATE"
, make the same procedure but select SYMBOL RATE at point
nr. 3.
To set the desired value, use the alphanumeric keypad or turn the shaft encoder. Press
ENTER
to confirm.
