Promax 10 SE, Руководство пользователя

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USER’S MANUAL. PROMAX-10 Premium
Page 22 11/2008
4.2.3.1 CHANNEL tuning
Figure 15.- V/A and C/N Level
measurement.
4.2.3.1.1 Video c V/A + C/N measurement (only for analogue
channels)
If the tuned channel has been defined as
analogue by means of the Edit Channel Plan function
(see section
4.2.1 Global Configuration Menu ), the
PROMAX-10 Premium will display a screen as the
one shown in the attached figure.
The tuned channel (C69 in the figure)
appears in the higher left hand corner; this may be
changed by turning the rotary selector [9]. At its right
appears the frequency (855.25 MHz) and the active channel plan (CCIR in the figure).
Below is shown the video carrier level , VIDEO Carrier (80 dBµV in the
example). The units of measurement may be changed using the Global Configuration
Menu (section 4.2.1). At the bottom, a bar-graph displays the level with a resolution of
1 dB.
Also the ratios between the video and the audio carriers (V/A) and the
video carrier and noise (C/N) are shown. The example in previous figure shows a
channel with a Video/Audio ratio of 16 dB and a C/N ratio of 54 dB.
Figure 16.- Audio demodulation
and measurement.
4.2.3.1.2 Audio carrier measurement and demodulation (only for
analogue channels)
For the PROMAX-10 Premium
to demodulate an audio signal and
show its characteristics (level and
frequency offset)
, press the rotary selector [9] again.
In the attached figure, the audio carrier level ( AUDIO
Carrier ) is 64 dBµV and the frequency offset is 5.50
MHz ( F ). It also shows if the audio (whether Level,
FM or AM) is activated (a speaker appears) or not (the
speaker does not appear). To change the audio carrier
offset (
F ) and the audio modulation (Level, FM or AM) access to the Channel-
Frequency configuration menu (section 4.2.3.3).