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CATV Quick Start Guide
HP 8712ET/ES and HP 8714ET/ES
HP Part Number 08714-90021
Printed in USA October 1998
© Copyright 1998 Hewlett-Packard Company
This quick start guide provides basic instructions on how to make measurements that test the quality of coaxial cables. Refer to the Option 100 Fault Location and Structural Return Loss Measurement
User’s Guide Supplement for more detailed information. Also, please refer to your analyzer’s User’s
Guide for safety, warranty, and assistance information.
NOTE This quick start guide assumes the use of an HP 8712ET or HP 8714ET. If you are using an HP 8712ES or
HP 8714ES, some key presses and displays will be slightly different.
To Make a Fault Location Measurement
1. Choose the measurement parameters or recall an instrument state.
PRESET BEGIN Cable Fault Location
Start Distance XX ENTER Stop Distance XX ENTER
3. Connect the equipment.
2. Calibrate the analyzer.
CAL Full Band Cal
-1-
4. View the fault location results.
5. Interpret the measurement / save results.
MARKER Marker Search Max Search
Mkr − > Max
Search
SAVE RECALL Define Save Data ON
Prior Menu Save State
To Make an SRL Measurement
1. Choose the measurement parameters or recall an instrument state.
PRESET BEGIN Cable SRL
2. Calibrate the analyzer.
CAL Full Band Cal
3. Verify the calibration.
Directivity is good if trace is below
−
50 dB.
Leave load connected.
-2-
Wiggle (move) the test-lead cable. The test-lead cable is good if the trace remains stable.
4. Connect the equipment.
5. Measure the connector.
BEGIN Cable SRL Connector Model
Measure Connector
6. Scan the cable.
BEGIN Cable SRL SRL Cable Scan
7. Interpret the measurement / save results.
MARKER Marker Search Max Search
Mkr − > Max
Search
-3-
SAVE RECALL Define Save Data ON
Prior Menu Save State
If Measurement Results Were Poor
The following results indicate some specific problems you may encounter. The 2nd and 3rd problem/solution are displayed using the “connector fault” feature. Refer to your Option 100 User’s
Guide Supplement for more information.
Problem 1
The measured amplitude and distance of a 1000 ft. cable are wrong. (Cable is not terminated in this example.)
Solution 1
Change the “velocity factor” and “cable loss” values to the values specified by the cable manufacturer.
Problem/Solution 2
The cable is bent near the connector (indicated by the 2nd bump in the “connector fault” response).
BEGIN Cable Fault Location CAL
Velocity Factor Cable Loss
Problem/Solution 3
The cable connector is failing or the cable is poorly prepared. Connector compensation fails to improve response.
Solution: Remove the bend.
-4-
Solution: Clean or replace the connector.
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