Reducing Measurement Error by Avoiding Cable Bending
1000BASE-T/100BASE-TX/10BASE-T Physical Layer Compliance Tests Manual
120
Intel Confidential
Cable Straight
Cursor 1 = 100.9
Cursor 2 = 101.7
Cable with 2” diameter loop in cursor area.
Cursor 1 = 101.7
Cursor 2 = 101.4
Note: A gentle bend has little affect.
Cable with half-knot in cursor area.
Cursor 1 = 94.3
; Cursor 2 = 96.3
Lower Z is caused by dielectric
compression (Conductors are closer
together).
Half-knot is untied & straightened.
Cursor 1 = 112.2
; Cursor 2 = 103.9
Higher Z is caused by “bird cage” effect
(Conductors are farther apart).