By pressing the Measure Cable Performance key, you can test Length/Delay, Impedance, Loop Resistance, Capacitance, Impulse Noise and Peak-to-Peak Noise for coaxial cable. NEXT and Attenuation are not supported for coaxial cable.

NOTE: The Injector is not used when testing coaxial cable.

Length/Delay Test Results

To display the LENGTH/DELAY screen, from the Ready screen, press Jack (F4) and set the Jack to Coax. Then press the Measure Cable Performance key, then select Length/Delay.

During the Length/Delay test, the cable should be open or shorted.

If NEF (No End Found) is displayed next to the Length, it indicates that the cable is properly terminated or the cable is too long.

The IEEE Length specification is 600 feet.

Press the ESCAPE key to exit.

Impedance Test Results

To display the IMPEDANCE screen, from the Ready screen, press Jack (F4) and set the Jack to Coax. Then press the Measure Cable Performance key, then select Impedance.

During the Impedance test, the cable can be open, shorted or terminated. There is no preference.

If UND (Under range) is displayed, the cable is less than 40 feet long or the Impedance is less than 40 ohms.

If OVR (Over range) is displayed, the Impedance is greater than 200 ohms, the cable is less than 40 feet long, or the cable/pair is not connected.

The IEEE Impedance specification is 50 ohms, ±2 ohms.

Press the ESCAPE key to exit.

Loop Resistance Test Results

To display the LOOP RESISTANCE screen, from the Ready screen, press Jack (F4) and set the Jack to Coax. Then press the Measure Cable Performance key, then select Loop Resistance.

During the Loop Resistance test, the cable should be terminated or shorted.

If OVR (Over range) is displayed, the Loop Resistance is greater than 10K ohms. The IEEE Loop Resistance specification is 14.6 ohms.

Press the ESCAPE key to exit.

Capacitance Test Results

To display the CAPACITANCE screen, from the Ready screen, press Jack (F4) and set the Jack to Coax. Then press the Measure Cable Performance key, then select Capacitance.

During the Capacitance test, the cable should be open.

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Microtest TSB-67 - 568A Annex E manual Length/Delay Test Results, Impedance Test Results