Planar IT-14, Руководство по эксплуатации

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You can return to SCAN measurement mode by pressing F2 key.
4.3.5 SPECTRUM measurement mode
This measurement mode is selected from SCAN mode by pressing F3 key. This mode displays spectrum
of the input signal in scaleable frequency range. See Figure 4.3.10:
Figure 4.3.10
On the screen you will see the following data:
1 – frequency of the frequency point indicated by marker
2 – command line with commands activated by
F1 , F2 and F3 keys
3 – measured level of the frequency point indicated by marker, in dBmV, dBuV or dBm
4 – marker
Adjust the marker position by
◄ and ► arrows. Select frequency range scale with F1 key from the
fullowing list:
a) . Spectrum diagram is in 13.750 MHz frequency range. LCD pixel corresponds to 0.125
MHz frequency range;
b) . Spectrum diagram is in 27.500 MHz frequency range. LCD pixel corresponds to 0.250
MHz frequency range;
c) . Spectrum diagram is in 55.000 MHz frequency range. LCD pixel corresponds to 0.500
MHz frequency range;
d) . Spectrum diagram is in 110.000 MHz frequency range. LCD pixel corresponds to 1.000
MHz frequency range;
Measuring of spectrum is pefrormed in 0.125 MHz step. When you choose
28MHz , 55MHz or 110MHz
frequency range several frequency points corresponds to one LCD pixel. In this case the frequency point
with the highest level will be dispayed.
Progress of spectrum measurement is indicated with white point run at the bottom of the spectrum
diagram.
You can return to SCAN measurement mode by pressing F3 key.
4.3.6 MER/BER measurement mode
The icon in the Main menu refers to this mode. This mode displays the table of the parameters
featuring the input DVB-T signal quality. The screen view is represented in the Figure 4.3.11:
Figure 4.3.11
On the screen you will see the following data:
1 – channel number
2 – selected frequency and frequency shift in MHz
3 – signal modulation parameters (subcarrier modulation type and subcarriers number)
4 – MER value in dB
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