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Page 18
Cable Length Meter
Changing Opens/Capacitance Coefficient Using Set Length
To change capacitance coefficients, follow the steps above (cable/wire must be
open) based on the sample wire (100 to 200 feet). The Cable Length Meter
measures the total capacitance of the cable and displays the value in the lower left-
hand corner of the LCD (the cable must be within 10 to 40 pf per feet range, other-
wise meter will indicate OL).
Table 4-3. Opens/shorts factory default values.
Mode Capacitance Opens Ohms per Feet/AWG Shorts
Coax 22.0 pf 0.0663 ohms/NA
Network 15.0 pf 0.0273 ohms/24 AWG
Telco 17.5 pf 0.0273 ohms/24 AWG
Figure 4-5. BNC-to-F connection for measuring coax.
4.4 Tone Mode
To generate a tone on the cable/wire, select Tone Mode (see Figure 4-6). The Cable
Length Meter has four unique tones. Use the UP/DOWN keys, to scroll through the
four tones. The tones generated match audio frequencies used with tone tracers/
probes. The signal generated on a pair is nominal 5 volts peak-to-peak across the
pair. The unit will power down automatically after 1 hour.
Available tones include:
1. High tone 1 KHz
2. Low tone 704 Hz
3. Warble tones, low tone for 160 ms, followed by 115 ms of high tone