Caller I.D. Vs. Privacy: Now There's A Middle Road

Until recently, right-to-privacy advocates slowed the spread of a service that phone companies think many customers will use. It's caller I. D., where a small device hooked to your phone displays the number of anyone who dials you. So when your phone rings, you have a good idea who's calling before you lift the receiver.

Available in 12 states, caller I. D. should be in 25 more by yearend, now that regulators are hearing how the technology can help customers keep unlisted numbers private. Such subscribers fretted that by the mere act of dialing, someone would discover their secret--making them a target for telemarketers. In response, caller I. D. systems now offer an "out": Before dialing, customers can press a sequence of buttons to block their number from showing up on a display.

Won't such blocking defeat the purpose of caller I. D.? Not if you have a new display unit from Colonial Data Technologies in New Milford, Conn. Its voice chip tells callers: "This party does not accept blocked calls." And the party's phone doesn't ring.

Offered by Ameritech, US West, Nynex, and other phone companies, caller I. D. typically costs residential customers about $5 monthly. A display unit costs as little as $30. If you want to prevent your number from showing up on a display, you pay a few cents each time you press the blocking sequence.

DIRTY TALK. With caller I. D., a cautious business owner can check whether someone placing a large order by phone is a real customer or a prankster. And if an anonymous caller voices threats or obscenities, you've got a number to give the authorities. Making things easier, an I. D. service unveiled last month by US West in Boise, Idaho, displays both the number and name of the person or company listed in the directory. In just 10 days, more than 300 residential customers signed on at $5.95 monthly, says a US West representative.

Caller I. D. is useful even if you own an answering machine, says Bill Diamond, marketing executive at Eagle Telephonics in Hauppauge, N. Y. That's because the I. D. unit picks up and stores the numbers of people who hang up when a machine answers.

Where the service is approved, phone companies and retail stores offer display units with various features and memory capacity. Most record the date and time of each call. A $90 model from CIDCO in New Rochelle, N. Y., has a lighted display for nighttime viewing. And it can store 64 numbers in order as the calls come in.

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