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Software Manual for the R&S ZVL-K1 - Rohde & Schwarz

Software Manual for the R&S ZVL-K1 - Rohde & Schwarz

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R&S <strong>ZVL</strong>-<strong>K1</strong> Cable TV Measurements (Option K20)<br />

Test setup:<br />

� Connect <strong>the</strong> R&S <strong>ZVL</strong>-<strong>K1</strong> to your CATV network.<br />

It is not possible to work without a channel table. You cannot even enter <strong>the</strong> TV Analyzer sub menu, if<br />

you have not activated a channel table be<strong>for</strong>e. Create a channel table according to you CATV network<br />

(or a subset of your network). This task is described in section Example: Creating a channel table. If<br />

you do not want to create your own channel table, you can use <strong>the</strong> example channel table from section<br />

Example: Creating a channel table, which is delivered with <strong>the</strong> Cable TV Measurements option.<br />

Procedure:<br />

1. Press <strong>the</strong> MENU key.<br />

2. Press <strong>the</strong> Channel Setup softkey.<br />

3. Select <strong>the</strong> appropriate channel table and activate it by pressing <strong>the</strong> Activate softkey.<br />

4. Press <strong>the</strong> MEAS key.<br />

5. Press <strong>the</strong> TV Analyzer softkey.<br />

6. Press <strong>the</strong> Tilt softkey.<br />

7. To restrict <strong>the</strong> channels to be measured, press <strong>the</strong> Tilt Setup softkey:<br />

The Tilt Setup dialog box is displayed.<br />

− To limit <strong>the</strong> frequency range, under Span, enter a start and stop frequency. Be sure that at least<br />

one channel's RF frequency is in this range. O<strong>the</strong>rwise <strong>the</strong> measurement display will be empty!<br />

− To select certain modulation standards <strong>for</strong> <strong>the</strong> measurement, under Modulation Standards,<br />

activate <strong>the</strong> modulation standards to be included in <strong>the</strong> measurement.<br />

8. To adjust <strong>the</strong> range of <strong>the</strong> y–axis, if logarithmic, press <strong>the</strong> Auto Range softkey.<br />

9. Press <strong>the</strong> RUN key.<br />

10. Observe <strong>the</strong> exact levels of different channels by turning <strong>the</strong> rotary knob.<br />

11. Check your network:<br />

− Do all signals of <strong>the</strong> same type (e.g. all analog TV signals) have similar levels?<br />

You can do this by selecting <strong>the</strong> modulation standards to measure be<strong>for</strong>e <strong>the</strong> measurement.<br />

Or you can measure all kinds of signals and distinguish different modulation standards after <strong>the</strong><br />

measurement by <strong>the</strong>ir different colors.<br />

− You can measure <strong>the</strong> amplitude response of <strong>the</strong> network (or of an amplifier) by looking at <strong>the</strong><br />

levels of signals at different frequencies. Prerequisite is ei<strong>the</strong>r that you measure be<strong>for</strong>e and after<br />

<strong>the</strong> amplifier and compare <strong>the</strong> results. Or that you know, that <strong>the</strong> levels are equal at <strong>the</strong><br />

transmitter.<br />

Channel Tables and Modulation Standards<br />

Measurements with <strong>the</strong> Cable TV Measurements option can be speeded up significantly if a channel<br />

table is used. First of all a channel table, sometimes also referred as channel plan, contains <strong>the</strong><br />

frequency plan of a cable TV network. Fur<strong>the</strong>rmore, <strong>for</strong> every channel it contains <strong>the</strong> in<strong>for</strong>mation about<br />

<strong>the</strong> service broadcast or <strong>the</strong> in<strong>for</strong>mation that <strong>the</strong> channel is < unused >.<br />

Typically every country has its own regulations concerning <strong>the</strong> frequency plan, i.e. <strong>the</strong> channel locations<br />

and <strong>the</strong> channel widths. Un<strong>for</strong>tunately <strong>the</strong> services or programs assigned to this frequency plan differ<br />

from one CATV network to ano<strong>the</strong>r. For example <strong>the</strong> CATV network of <strong>the</strong> city of Munich offers different<br />

programs than Erding which is only about 40 kilometers away. There<strong>for</strong>e <strong>the</strong> Cable TV Measurements<br />

option provides empty channel tables <strong>for</strong> most countries in <strong>the</strong> world, where empty means, that all<br />

1303.6573.42 2.81 E-5

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