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The 4mm plug to BNC adapter accessory is for use on cable distribution systems and low voltage cables only. The operator must verify that
the circuit is safe for testing and take the appropriate precautions.
In the event of no reflections being visible, increase gain in setup mode until any reflection can be easily identified. (If no reflections can be
seen, try shorting or earthing the far end of the cable to ensure that you are “seeing” the whole length of the cable).
The range may be changed by moving the four-way switch up and down and the cursor moved using the LEFT and RIGHT joy switch. Move
the cursor to the beginning of the reflection. The distance to the fault can then be directly read from the display.
The distance calculation is performed using the velocity factor set in the TDR. If this velocity factor is not correct for the cable under test, the
displayed distance will be incorrect.
Shown are two typical trace displays. The first shows an open circuit; the second a short circuit.
