Cable TV Measurements (Option K20) R&S FSL
1300.2519.12 2.64 E-11
Procedure:
1. Press the SWEEP key.
2. Press the Single Sweep softkey.
3. Press the FREQ key.
4. Enter 210.25 MHz for the vision carrier frequency of the input signal.
5. Press the MEAS key.
6. Press the Analog TV softkey.
7. Press the CTB softkey.
8. To change the limits, press the Edit Table softkey.
9. To adjust the input attenuator, press the Adjust Attenuation softkey.
10. Press the CTB Setup softkey to open the CTB Setup dialog box.
Specify a single span for the beat measurement: Change the CF value, which denotes the
middle of the span relative to the vision carrier and the Span value in the table. The
measurement range should be centered around frequencies where you expect triple order beats
in your network, i.e. the CF value should normally be about 0 Hz.
If desired, activate the Noise Floor Correction option.
11. Press the RUN key.
12. Turn on the signal when prompted and confirm by pressing the ENTER key.
The R&S FSL will measure the carrier power. This is not visible on the screen.
13. Turn off the test transmitter or remove the cable when prompted and confirm by pressing the
ENTER key.
The R&S FSL will measure the beats in the span specified in the CTB Setup dialog box.
14. Using the rotary knob, move the marker to the frequency you want to measure the beat at. The beat
level at this marker is measured and used to compute the CTB ratio. You should take care not to
measure a CSO beat instead of a CTB beat.
Fig. 2-43 CTB measurement
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