When the telephone tapped is yours

One phone tap in America turned out to be at our home, in a Washington suburb; it lasted from mid-November of last year until the end of January. Phones can be tapped silently so that their users never know they are being listened to. Our tap was audible - the work of an amateur.

In our subdivision all phone wires are underground. The line to our house rises out of the ground next to the garage and follows the wall about three feet before tunneling inside. This wire was tampered with; three layers of insulation were neatly cut away. This area was wrapped in black electrical tape, and two slender wires - our phone line - had ``penetration'' of their thin plastic insulation.

Experts say tiny clips probably were used to fasten an electronic device that added a hum to our line. The tapper then went to the backyard post at which our line and those of three nearby houses are connected to the underground cable. A device likely was used to listen to the lines: The one with the hum was ours.

Three factors indicate that our phone line was connected at the backyard post to wires carrying our conversations to a spot where they were recorded:

Shiny nicks in the nuts that fasten our wires to the main cable; a pair of loosened nuts directly below ours; an extra set of wires within the hollow metal post unconnected to anything. Standard phone company procedure is to snip off such uninsulated ends to prevent short circuits. Experts think these wires had been attached to the loose nuts; anyone then could monitor the other ends of these now-extra wires wherever they emerged from underground.