11
to the selected channel plan. If a channel plan has not been selected, the modulation type
is detected automatically.
Three analog channel parameters are measured. Video carrier level at the frequency
tuned. If a channel plan has been selected, the frequency tuned will follow the selected
plan. Vision to Audio ratio is determined by also measuring the audio carrier level and
subtracting this value from the video carrier. The V/A value will be displayed on the screen
in position 4 (Figure 4.3.5).
To measure analogue Carrier to Noise ratio the Analyzer compares a measurement at
the tuned frequency with the lowest content of the useful components of RF signal within
the channel bandwidth. C/N ratio will appear in position 8 (Figure 4.3.5).
For digital channels, the Analyzer measures signal power within the channel bandwidth
and C/N ratio. To measure C/N ratio, the Analyzer compares a measurement at the tuned
frequency with the lowest content of the useful components of RF signal outside the
channel bandwidth. C/N ratio will appear in (Figure 4.3.6).
The range of voltage measurement at the Analyzer input is from 10 to 100 V. The
absolute error of the measurement is lower than ±1.5 V. The measured value of the
voltage is indicated in position 7 (Figure 4.3.5). If the voltage is DC you will see
V=
on the
screen, if it is AC
V~
will appear.
To measure channel parameters, select the required channel by ◄ and ► arrows.
If no channel plan is selected, using ◄ and ► arrows you can switch to any channel in
accordance with the channel template (Section 4.7).
Once a signal is detected, the Analyzer will automatically determine the channel type.
The measurements will be performed in accordance with these parameters.
If a channel plan has been selected (Section 4.5), the selection will be performed
between the channels of the plan.
You can access other measurement modes using functional keys.
F1
key will open
SCAN mode (Section 4.3.3).
F2
key will activate the mode of signal level measurement in
a frequency point.
F3
key will open MER/BER measurement mode (Section 4.3.6), if the
selected channel is digital.
