49
To save the measured results and the current settings of the program into a file, select
«Save»
in
«File»
menu. If the data were not saved before, the standard dialogue box
for file saving will open. Set the file name and its location. Click
«OK»
to confirm saving.
The name of the currently open file will be displayed in the title bar of the program.
To download previously saved data use
«Open»
in
«File»
menu. The standard
dialogue box for file opening will appear. Find the required file and click
«OK»
. The
scanning process will be stopped and the program settings will be downloaded and the
curves of the saved data will appear. The name of the opened file be displayed in the title
bar of the main window.
4.10.7. Channel Diagram
4.10.7.1. General Information
The channel diagram (figure 4.41) displays the signal levels measured in frequency
points, which are defined by the current channel plan, as vertical bars. The height of the
bars corresponds to the measured levels, the position of the bars corresponds to the
frequencies.
Figure 4.41
When you place the mouse pointer over any bar of the channel diagram, the information
on this channel will be displayed in the upper left corner of the diagram. It represents a text
line containing number and name of the channel, video carrier level (of actual channel
level for digital channels), V/A ratio (for analogue channels) and C/N ratio.
In the upper right corner, the TV system and selected channel plan information will be
indicated.
The diagram is also used for setting of the viewing area limits of the spectrum. Using
the control elements of frequency and level scales you can set the area to be displayed in
the spectrum diagram. To adjust the level display limits, drag the corresponding scale
sliders by the mouse. To adjust both limits simultaneously press and hold
«Shift»
key on
the keyboard. To set the frequency limits, proceed as above dragging the scale sliders
along the frequency axis. The spectrum display area will be represented as the area not
colour highlighted.
To change the height of the panel place the mouse pointer on the line between the
channel diagram and the spectrum panel. The pointer will change its form. Then press left
button of the mouse and holding it drag the line to a new position, then release the button.
The panel will change its height.
4.10.7.2. Channel Plan Selection
You can define up to 32 channel plans numbered from 1 to 32. The frequency set in
different channel plans can be different. The frequency points as a rule correspond to the
TV carrier frequencies or to central frequencies in digital channels. The channel diagram
can also use a non editable channel plan number 0, with the frequency assembly of up to
112 frequency points of the current TV system. To select a channel plan, perform the
following:
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