Quick Start Guide for AV3680A Handled Cable & Antenna Tester
DTF (Distance To Fault) measurement, also called fault point location measurement, is a kind of
performance verification and fault analysis tool in the maintenance and repair process of antenna and
transmission line. DTF function of AV3680Ais realized by adopting the measurement technique named
Frequency-Domain Reflectometry. In engineering applications, DTF measurement usually adopts the
connection type shown in Figure 3.13 to measure the fault point status of connection cables of devices
such as base stations, etc.
Antenna
Connector
Fault Point
Figure 3.13 DTF Measurement Connections
AV3680A provides two measurement formats including DTF return loss and DTF VSWR. As for their
difference, we will not explain here again for it is similar to the difference between return loss and VSWR.
We will make a detailed introduction for measurement steps on cable length and return loss at each point,
through taking the cable with length of 25m, velocity factor of 0.76 and cable loss of 0.26dB/m.
1. Press
【
MEAS
】
to enter the measurement menu;
2. Select [DTF Return Loss] menu to set the current measurement format to “DTF Return Loss”, as shown
in Figure 3.14.
Figure 3.14 Measurement Format Select
3. Press
【
FREQ/DIST
】
to enter the frequency menu; select [Start Freq] menu, then use the numeric
keys, knob or arrow keys to input the start frequency value and select the corresponding unit menu to
complete the input; the frequency in this example is set to 1GHz.
4. Similar to step 3, set the stop frequency needed by the measurement; the frequency in this example is set
to 2GHz, as shown in Figure 3.15.
