The A-Bug brand Model 140 Tone Probe is an advanced technology probe that detects and amplifies audio tones in the 500 to 5000 Hz range (thus eliminating mains hum), and is used by cable technicians for pair identification, cable pair tracing and fault location in telephone LAN and other metallic cables. The Tone Probe uses a non-metallic capacitive tip to non-intrusively detect tones without metallic contact

Typical applications include:

• Identification of individual pairs in outside plant cables at splices, terminals, cabinets, and pedestals

• Tracing of jumper wiring in central office bays and main distribution frames

• Tracing of station wiring, cables or key equipment terminations in equipment rooms and distribution terminals

• Identification of drop wires and buried service wires at terminals an pedestals

• Location of wiring in walls

• Location of opens in wires

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  RScomponents are selling these for £60 each without headset and holster.