TV's watching you. Now that remote controls and VCRs have made commercial-zapping easy, broadcasters are using a controversial high-tech device to find out if viewers are really paying attention when the set is turned on.

Questions about who is watching television commercials in these days of widespread remote controls, pay-cable channels, and VCRs has brought Big Brother to America in a form George Orwell could not have predicted - the ``people meter.'' In recent months, as the people meter has supplanted older ratings systems, thousands of carefully selected ``typical'' TV-watchers have allowed ratings companies to install high-tech automatons in their homes - surveillance equipment that records not just what their TV set is tuned to but who is watching and, in some cases, what products are purchased by the household.

It knows if you leave

The equipment then transmits the information to computers at ratings companies, which correlate and sell the information to broadcasters, who use it to set rates for the commercial time they sell to advertisers and to decide which programs will survive. Ad agencies also buy the information to determine where to air their commercials.

The most sophisticated people-meter systems include a heat sensor that detects when anyone enters or leaves the TV room. When somebody does, the system flashes a question on the screen, ``Who is watching?'' and then interrupts viewing until an answer is punched into a response panel.

The equipment also electronically records, on a second-by-second basis, when viewers turn the set on or off, change channels, use a VCR, or even fast-forward through a commercial.

Roger D. Percy, a young entrepreneur whose new Seattle-based service, R.D. Percy & Co., has made waves in the ratings industry with use of this equipment, says his system is designed primarily to give advertisers specific commercial ratings never before available. He can tell them which position in a ``pod'' of commercials fares best (usually the first and last), and which commercials hold viewers' attention best.

Fewer `brutalizing' ads

Some commercials receive from 17 to 30 percent lower ratings than the programs on which they appear, he notes.

Asked, during a Monitor interview at the company's New York office, what the people meters will do for viewers, Mr. Percy, son of ex-Sen. Charles Percy of Illinois and brother of Public Broadcasting Service board member Sharon Percy Rockefeller, says, ``Well, programs which are ... more valuable will naturally get higher ratings and tend to stay on the air longer. And advertising will change.

``For years, advertisers subscribed to the philosophy that, even if the ad is boring, you can brutalize the public with it and, by showing it constantly,can almost force the public to buy the product. Now that over 50 percent of [US] households have remote-control devices, the viewer has the capability of not sitting through an ad he feels is boring, abrasive, or redundant.

A lesson for Madison Ave.

``The viewer - with the help of the remote-control device - is now teaching Madison Avenue a lesson. He is saying: `Show me something I want to watch. Entertain me, or in-form me. Just don't brutalize me.' One of the most important things broadcasters may learn is that they are putting too many commercial breaks into programs right now.

``Twenty-two billion dollars' worth of free TV is based on the hypothesis that, if we can count the number of people watching a show, they are all watching the commercials. That may have been true in the 1960s and '70s. Now, with remote control, that's changed.''

Indeed ``flippers,'' ``zappers,'' and ``zippers'' have thrown all the old viewership assumptions into doubt. (Zappers are the people who use their remotes to silence commercials; flippers keep busy sampling what various channels have to offer, especially during commercial breaks; zippers record the programs they plan to watch and then fast-forward through the commercials on playback.)

According to Percy, VCRs are now in close to 50 percent of all US households, and nearly 60 percent have remote-control devices. ``In high channel-changing households, we find as many as 3,000 channel changes a day,'' Percy says.

The heat-sensor technology introduced by the Percy company was at first denigrated by the older ratings services, which charged that the patented Percy Voxbox 1200 could mistake a large dog for a human viewer. ``Yes,'' says Percy, who worked for the McCann-Erickson ad agency before launching his company, ``we could make that mistake - but only if a hairless, 80-pound dog came walking in on two feet and punched himself in.'' The three other major ratings systems - A.C. Nielsen, Arbitron, and AGB Television Research Inc. - now either have added, or are adding, heat sensors to their people meters.

It was last Aug. 31 that the leading ratings organization, Nielsen Media Research, began basing its results on people meters rather than on the ``passive'' boxes that had been used earlier to record which channel the set was tuned to when it was on. Nielsen's switch to people meters hasn't been total, however; the company still relies on ``diaries,'' in which viewers note on paper what programs they watch, for local-channel ratings in ``sweeps'' periods, when local advertising rates are set.

Even so, more than 2,500 US homes are now fitted with Nielsen meters. With the three other services added in, an estimated 10,000 people meters are now monitoring America's television households.

Like Percy, all three other services now use push-button people meters, which require the viewer to announce his presence and the presence of others in the room. Arbitron has an added service for advertisers: a data-scan wand that logs product-purchase information when householders pass the wand over the bar codes on the packages from the supermarket bag.

The Percy system is now available only in New York, but Percy says he expects to have it ready within a year in Los Angeles and Chicago and still later in seven other major markets.

He admits that even a highly sophisticated system like his can only verify whether a viewer is in front of the set when a commercial airs. Whether or not his eyes are on the screen, the people meter cannot tell. ``But certainly it is better than if you were in another part of the house,'' Percy says. ``We ask people to tell us who they are when they turn on the set - all they get is audio until they tell us who they are. If they leave the room without keying out, after a while the screen will ask if they are there. If they log themselves out and remain, the passive screen will say I see somebody here. Our system makes it difficult to fool us.''

Nonetheless, people-meter families may try. One person with a people meter attached to her TV - we'll call her Debbie, since she wishes to remain anonymous - allowed us to take a look at the setup in her home, despite the fact that the company's rules prohibit that.

Debbie receives $20 a month for allowing her set to be metered, but she says she's not doing it for the money. ``I am allowing this equipment in my home,'' she explains, ``because I feel it is a chance to have some input into a medium which is becoming more and more important in our culture.

``We watch mostly PBS and, on cable, Arts & Entertainment.... This is my chance to let the people who put on the programs know what I want. So I turn on PBS, even when I'm not that interested, just to keep it up there in the ratings.''

Debbie says the company's request that she keep her people-meter status a secret from her friends is ``completely unrealistic, because anybody who comes into my house and sees the extra equipment and watches me punch information into it is going to demand to know what is going on.'' The meter consists of a remote control with push-buttons; a 3-by-5-by-8-inch gray box with sensors on top of the set; a 3-by-10-by-13inch black box under the set; and a 3-by-8-by-10-inch black case near the phone.

The equipment automatically stores information and then transmits it in the middle of the night, using Debbie's telephone line. ``It's a little unnerving to hear it click away in the wee hours of the morning sometimes,'' she says. But it does not really disturb her, since she was assured that there is no two-way eavesdropping capability. Yet, when the phone rang during her conversation with this reporter, and there was nobody at the other end, she asked, ``Do you suppose that's Big Brother warning me?''