"Vote 'no' to robots. Dial '0' -- the human touch."

So goes the slogan being used by telephone workers in their nationwide campaign against automation that they fear could lead to the elimination of the human operator.

Technology has been slowly replacing human operators for decades. But it just recently moved into one of the last domains of the human operator -- collect phone calls.

A new service being offered by phone companies around the country turns customers trying to place collect calls over to a computerized voice.

The computer asks the caller to punch in the phone number of the person they are calling and to give their name at the sound of the tone. The call is then placed electronically, bypassing any human involvement.

Fearing increased job losses from such services, the Communication Workers of America is urging consumers to fight the automation.

One union ad in a newspaper depicts an image of "Star Wars's" Darth Vader adorned with an operator's headset beside a quote saying, "Ma Bell wants you to take orders from a robot."

Steve S. Rosenthal, spokesman for CWA, said that the number of human operators has diminished from about 400,000 in the 1950s to about 75,000 now.

"We are not saying that they will eliminate human operators tomorrow, but there have been a series of steps toward this.

"First, it was directory assistance, which is now partially automated; then credit card calls, wherein initially you get an operator, now you get automation," said Rosenthal.

The CWA says it fears that the use of automation will eventually eliminate human operators completely.

Bell Atlantic Corp. spokesman Lawrence D. Plumb said the regional operator has already automated half of the D.C. area with the new system for placing collect and third-person calls.

Plumb also said that the company has no intention of eliminating human operators, but he also declined to give any figures on cost savings.

The CWA has argued that the increased use of automation in operator services could lead to critical situations in certain emergencies.

Rosenthal said that operators have endless stories about receiving calls from heart attack victims and being able to respond in ways that a computer could not. The union said the technology also invites more obscene calls since a person making a collect call using the computerized system can leave an obscene message with the automation technology.

The threat of eliminating operators appears more real in the long-distance market. American Telephone & Telegraph Co. spokesman Rick Reser said the firm will eliminate 1,000 telephone operators this year, bringing its total to 19,900. In 1988, At&T had 21,900 operators.

Reser said AT&T will continue to provide customers the option of using a human operator.

AT&T handles 85 million calls a day, 6 million of which are coursed through operators, he said.

Of the seven regional companies, only US West is not using automation in its operator service.