Planar IT-100 Operating Manual page 21

4.3.3.2. Digital channel measurement
Digital modulation channels feature measurements of actual channel power level in
the channel allocation bandwidth and TV channel reception quality parameters in numeric
form and in the form of vertical bars (figure 4.7).
The following data is displayed on the screen: tuning frequency and frequency offset
(CR), actual channel power level in the channel allocation bandwidth (P) and measured
reception quality parameters, such as modulation error ratio (MER), MER margin to quasi
error-free reception threshold (MARGIN), uncorrected MPEG packets rate and quantity on
demodulator output (PER/CNT). The following parameters of decoders are measured for
different standards:
1) DVB-C and J.83-B/C. Bit error rate before Reed Solomon decoder (CBER);
2) DVB-T. Bit error rate before Viterbi decoder (CBER) and after Viterbi decoder
(VBER);
3) DVB-T2. Bit error rate before LDPC decoder (CBER) and after LDPC decoder
(LBER).
UPTIME parameter shows elapsed time since TV channel was locked. In case a
parameter value is outside the limits of selected limit plan (section 4.3.13), it is indicated
with red background.
Level value and MER values are indicated in graphical form in left part of the screen.
The bar height indicate current parameter value, and markers indicate minimal and
maximal parameter value achieved.
Channel selecting is performed with the «◄» and «►» key pressing. When pressed
with «Shift» holding, channel is changed with bigger step. Channel can also be selected
by typing its number with alphanumeric keyboard.
When a channel is selected, the Meter will automatically detect the standard and
modulation parameters. It is recommended to use channel plan (section 4.3.12) in order to
make synchronization faster.
To set up the mode, press «F1 / Settings». The following parameters are available
for editing in the dropdown menu:
1) Ref. level. Selection of reference level value. Possible values are 50 to 120 dBuV
and Auto. The setting resolution is 10 dB. The parameter sets up the maximum
possible measured signal level;
2) Level scale. Setting level histogram division value: 2, 5, 10 or 20 dB;
3) Averaging. Selection of measured parameters averaging factor: Off, Low,
Medium, High;
4) Sound indication. Selecting the parameter value sound indication type: off –
switched off, Tone – sound frequency is proportional to parameter value, Pulse –
pulse repetition rate is proportional to parameter value;
Figure 4.7
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