Anritsu S251C manual Distance-To-Fault DTF Transmission Line Test, Procedure DTF-Return Loss Mode

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Chapter 4 Measurements

Distance-To-Fault (DTF) Transmission Line Test

The Distance-To-Fault transmission line test verifies the performance of the transmission line assembly and its components and identifies the fault locations in the transmission line system. This test determines the return loss value of each connector pair, cable component and cable to identify the problem location. This test can be performed in the DTF–RE- TURN LOSS or DTF–SWR mode. Typically, for field applications, the DTF–RETURN LOSS mode is used. To perform this test, disconnect the antenna and connect the load at the end of the transmission line.

Required Equipment

Site Master Model S251C

Precision Open/Short, Anritsu 22N50 or Precision Open/Short/Load, Anritsu OSLN50LF

Precision Load, Anritsu SM/PL

Test Port Extension Cable, Anritsu 15NNF50-1.5C

Optional 510-90 Adapter, DC to 7.5 GHz, 50 ohm, 7/16(F)-N(M)

Device Under Test

Transmission Feed Line with Load

Procedure - DTF-Return Loss Mode

The following steps explain how to make a DTF measurement in return loss mode.

Step 1. Press the MODE key.

Step 2. Select DTF-RETURN LOSS using the Up/Down arrow key and press ENTER. Step 3. Set the start and stop frequencies, F1 and F2, as described on page 3-2.

Step 4. Connect the Test Port Extension cable to the RF Out port and calibrate the Site Master as described on page 3-2.

Step 5. Save the calibration set up (page 3-5).

Step 6. Connect the Device Under Test to the Site Master phase stable Test Port Exten- sion cable. A trace will be displayed on the screen as long as the Site Master is in sweep mode.

Step 7. Press the FREQ/DIST key.

Step 8. Set the D1 and D2 values. The Site Master default for D1 is zero.

Step 9. Press the DTF AID soft key and select the appropriate CABLE TYPE to set the correct propagation velocity and attenuation factor.

NOTE: Selecting the right propagation velocity, attenuation factor and distance is very important for accurate measurements, otherwise the faults can not be identified accurately and insertion loss will be incorrect.

Step 10. Press SAVE DISPLAY (page 3-5) name the trace, and press ENTER.

Step 11. Record the connector transitions.

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Contents Site Master Model S251C Antenna Cable Analyzer Page Warranty Page Table of Contents Cable & Antenna Analysis Iii/iv Description Standard AccessoriesIntroduction Options Optional AccessoriesPerformance Specifications Description Site Master Performance Specifications 2 ESD Precautions Preventive MaintenanceAnnual Verification Anritsu Service Centers Chapter Functions and Operations Test Connector PanelActive Function Block Soft Keys Front Panel OverviewMode Function Hard KeysClear Keypad Hard KeysAuto MODE=FREQ FREQ/DIST Softkeys Soft KeysMODE=DTF FREQ/DIST Softkeys Functions and Operations Amplitude MODE=POWER Monitor Softkeys Power Monitor Menu OptionMODE=RF Source Softkeys RF Source MenuLimit Segment 1 Segment SYS Self Test SymbolsSelf Test Errors Error CodesERRORD2 Range ErrorsCharging a New Battery Battery InformationCharging the Battery in the Site Master Charging the Battery in the Optional ChargerBattery Life Battery Charge IndicatorImportant Battery Information Chapter Getting Started Power On ProcedureCalibration Select the Frequency or DistanceCalibration Calibration Procedure Single PortRF in Test Port RF OUT Test Port Calibration Procedure Dual PortSave and Recall a Display Setting the ScaleSave and Recall a Setup Recalling a Display Changing the Display Language Set the Distance and Cable TypeChanging the Units Printing a Screen PrintingPrinter Printer Switch SettingsUsing the Site Master Soft Carrying Case Using the Soft Carrying CaseLine Sweep Fundamentals One Port MeasurementsMeasurements Information Required for a Line SweepSystem Return Loss Measurement Typical Line Sweep Test Procedures2is an example of a typical system return loss trace Insertion Loss Measurement Procedure Cable Loss ModeType Attenuation dB/ft Length ft = Loss dB Procedure Return Loss Mode Procedure DTF-Return Loss Mode Distance-To-Fault DTF Transmission Line TestProcedure DTF-SWR Mode Antenna Subsystem Return Loss Test Vswr Introduction Two Port MeasurementsTMA-S TMA MeasurementsTMA Gain Measurement After Calibration TMA-DD 12. TMA-DD Gain Measurement TMA-D 14. TMA-D Gain Measurement 15. System Isolation Antenna to Antenna IsolationAntenna-to-Antenna Isolation Measurement Quency settings for common systems21/4-22 System Requirements FeaturesCommunication Port Setting InstallationDownloading Traces from the Site Master Using Software ToolsInterface Cable Installation Plot Properties Plot CaptureSaving Traces Trace Overlay or Plot OverlaySaving a Plot to a Spreadsheet Custom Cable ListPrinting Formats Creating a DatabaseAppendix a Reference Data Coaxial Cable Technical DataAppendix a Reference Data A-4 Examples Appendix B WindowingAppendix B Windowing B-4