Advanced Wiretap Detector lets you quickly and easily check both single and two line phone systems for series and parallel taps. This advanced unit tests every possible combination of wires in a four wire cable. This lets you detect some of the more sophisticated taps that use split pairs. This device will also check your telephone for the most common types of hookswitch bypasses. A hookswitch bypass is a modification to the telephone instrument so that the carbon microphone (transmitter) or dynamic earphone (receiver) will pick up room sounds and pass them down the phone line to a listening post even with the phone hung up. This effectively turns the telephone into a room monitor.
This device will let you check your on-premises wiring and telephones for eavesdropping devices or taps. In order to do this, you must be able to disconnect your inside wiring from the telephone line coming into your home or business. This is done at the interface between the telephone line and inside wiring; usually just by unplugging a cable at the interface box mounted on the side of the building. There is nothing difficult about this, but, of course, you must have access to this interface box. An instructional manual comes with this device for a detailed information on how to install.