Fig. 79 Power Sum ACR-F (Power Sum ELFEXT)
6.10.1
NEXT Test and ACR-F (Power Sum ELFEXT) Test Error
Crosstalk is usually caused by faulty connections at the cable ends. The lower the
measuring values in dB, the stronger the crosstalk.
6.11
Insertion Loss Test (Attenuation)
This test determines the overall insertion loss of the signal in the cable and checks
compliance with limits. A minor loss is the prerequisite for a faultless transmission. Insertion
loss measurement is performed by feeding a signal with known amplitude into the Remote
handset (RH) and then reading the amplitude on the Display handset (DH).
6.11.1
Insertion Loss test Error
The insertion loss reduces the signal in the cable. Loss increases with cable length, signal
frequency and temperature. With the aid of loss tests it is possible to detect faults in cable,
connections and connection technology. A high loss value in dB indicates a strong loss, and
thus a higher signal reduction.
6.12
Return Loss Test
This test determines the relation between reflected and transmitted signal amplitude. High-
grade cable lines exhibit only minor reflection, thus demonstrating a good impedance
adjustment of the individual components connected to the cable.
LanTEK III
User Manual
Fig. 80 Loss Test
161809 Iss 2
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