Specifications

122 Chapter 14
Demodulating and Viewing Television Signals (ESA-E Series Option B7B)
Demodulating and Viewing Television Signals
Demodulatin
g
and Viewin
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Television Signals (ESA-E Series
Option B7B)
Demodulating and Viewing Television Signals
ESA-E Series with option B7B (TV trigger and picture on screen) allows
you to trigger the sweep of the analyzer on a specific television line of a
demodulated TV waveform. Option B7B also allows you to view the
television picture represented by the TV waveform on the color LCD
display of the analyzer.
This procedure sets up the analyzer to trigger on the TV video
waveform and to view the picture of the TV signal on the analyzer.
For more information on TV trigger setup see the concepts chapter “TV
Trigger Setup Menu Functions” on page 154.
Step 1. Connect a source which contains suitable TV carrier signals (for
example, terrestrial broadcast or CATV signals).
Step 2. Disable the background alignment process while viewing TV pictures:
Press
System, Alignments, Auto Align, Off.
This is necessary to prevent the background alignment process from
interrupting the signal paths of the analyzer during the sweep retrace
period so as to maintain a constant, uninterrupted video waveform.
NOTE After viewing the TV waveform or picture, re-enable the background
alignment process by pressing
System, Alignments, Auto Align, All. If the
background alignment has been disabled for more than 60 minutes or
the ambient temperature has changed more than 3 degrees centigrade,
press
System, Alignments, Align Now, All to ensure measurement
accuracy. See the Specifications and Characteristics Chapter for your
analyzer model in the specifications guide, for information about
alignment requirements.
Step 3. Set the center frequency of the analyzer to match the TV video carrier
frequency and set the span to 20 MHz to capture the TV channel:
Press
FREQUENCY Channel, then enter the desired value and units.
Press
SPAN X Scale, Span, 20, MHz.
Step 4. Auto couple the analyzer settings:
Press
Auto Couple, Auto All (if present, newer software only).
Step 5. Adjust the reference level of the analyzer to the peak video carrier level:
Press
AMPLITUDE Y Scale, then use the knob or step keys.
NOTE If the signal is weak and accompanied by excessive noise, you may
choose to enable the internal preamp, if installed, to improve the
signal-to-noise ratio. Press AMPLITUDE, More, Int Preamp (On).