Publicidad
Idiomas disponibles
Idiomas disponibles
Digital channels :
To access to this mode of operation, press the CH-FR key [10]. There exist two
tuning modes : by channel or by frequency . To switch the tuning mode press the
CH-FR key [10].
4.2.3.1
Channel tuning
4.2.3.1.1
Video carrier + V/A + C/N measurement
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 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.
4.2.3.1.2
Audio carrier measurement and demodulation
For
the
demodulate an audio signal and show its
characteristics
(level
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 (no
icon appears). To change the audio carrier offset ( F )
and the audio modulation (Level, FM or AM) accede to the Channel-Frequency
configuration menu (section 4.2.3.3).
Page 22
- Channel power by measurements integration
- Carrier / Noise (C/N) ratio
- Bit error rate (BER)
- Modulation error ratio (MER)
- Constellation Diagram
PROMAX-10
to
and
frequency
USER'S MANUAL. PROMAX-10
Figure 13.- V/A and C/N Level
measurement
Figure 14.- Audio demodulation
and measurement.
04/2004
Publicidad
