Coaxial Impedance Error "Cable Too Short"

Coaxial testing with the DSX CableAnalyzer using the DSX-COAX modules includes the following autotest measurements:

  • 長さ
  • Resistance (remote or terminator required)
  • インピーダンス
  • 挿入損失
  • 伝搬遅延
  • HDTDR アナライザー

When testing Impedance, the minimum cable length for an impedance measurement is 13ft / 4m.  The impedance measurement shows the approximate characteristic impedance of the cable at a point approximately 13 ft (4 m) from the tester.

Testing coaxial cable lengths shorter than 13ft/4m the test results will show “Cable Too Short” in the test reports.

 

On the Versiv tester, the same result will show "i" (information only) for the impedance and overall test results.  Good cabling has relatively constant characteristic impedance throughout the cable and connectors. Changes in impedance cause signal reflections in cabling. In computer networks, signal reflections can cause network faults. In video systems, reflections can cause poor picture quality.