This is the other side of the Television Presidency, here at 5:52 p.m. in an old high school in Parkersburg, W. Va. CBS producer Susan Zirinsky has 38 minutes to go before the "Evening News" and, as usual, she's on the ragged edge of disaster.

She and CBS White House correspondent Bill Plante have spent the day with the president, and after three cities in eight hours, the story she has to edit and send to New York is still in stacked cassettes on the floor of room 218, currently her makeshift, on-the-road studio. She has finished off her last two Tylenols and now feels the familiar pre-broadcast gnawing in her stomach.

"When I first started working, I was panicked all the time," she says. "I even went to a psychiatrist. But then I thought, 'Maybe it's better to be nervous. It gives you an edge.' "

Zirinksy is a 32-year-old, 5-foot-2 compulsive mother hen who calls colleagues "pumpkin," swears like a truck driver and looks like a schoolgirl. Her computerized editing equipment is set up on the teacher's desk. She rapidly selects shots of the balloons and cheering crowds that the White House has expertly planned for the cameras. She scarcely has time to edit, let alone filter out all the propaganda.

Plante is writing his narration at a table against the blackboard, trying to find a nugget of news. He's having his usual fight with Zirinsky, although it's nothing compared with the day he threw his walkie-talkie at her. She wants to include some Reagan hecklers in the piece; Plante thinks there weren't enough to be important. She appeals to New York, loses, then looks at Plante's "stand-up," a shot of him talking in front of Air Force One. She tells him she's going to make it shorter.

"It's only a sentence," he grumps. "How much are you going to cut?"

"This is like being married to someone," she mutters.

At 6:15, they're finished. The story's theme is that Reagan is warning his supporters against complacency but also trying to bring a Republican Congress in on his coattails. The pictures are as glorious as any advertising spot: bands, pretty children, the president's sleek limousine.

"Sometimes you can't help making it look like a commercial," Zirinsky sighs. "What I really try to fight is just coughing up what they've given you. But the White House doesn't stack the audience with pretty kids. That's America. I'm going to use the best pictures I have. If Ronald Reagan looks good, what can I do?"

Television news is one of the most important battlegrounds in American politics, and Susan Zirinsky is one of the best field commanders in the business. She hires Lear jets, tells Lesley Stahl to change her stand-up and slicks down Bill Plante's hair when it won't stay put. She is on the literal cutting edge where news judgment wars with the packaged images of a president who uses television with phenomenal skill.

Every day of the campaign, the White House settles on the presidential theme -- leadership, taxes -- that it would like to get out, spending hundreds of thousands of dollars on planning and staging, all in the hope that it can get two favorable minutes on the network news. As Zirinsky herself says, "If we didn't get it on the air, did it happen?" At the same time, the networks are planning their own assault, spending hundreds of thousands of dollars on helicopters, chartered planes and camera crews.

"If you go two weeks back, I don't think we won once," says White House Chief of Staff James A. Baker III, referring to the days right after Ronald Reagan lost the first debate to Walter Mondale. "We did not have our story on the nets as we would have liked. We were totally on the defensive. What was amazing to us is that the polls hung up there as well as they did."

"Most days the White House wins," counters Lane Venardos, the executive producer of the "CBS Evening News." "Most days the president doesn't make a mistake. So it's their agenda."

Susan Zirinsky, who has been working regularly on the White House beat since Reagan became president, is right on the battle line. Although it is Bill Plante and Lesley Stahl who cover the White House, write the stories and appear on the air, it is Zirinsky who decides on the pictures that as many as 25 million people will see each night in their homes. And as any campaign official will tell you, it's often the pictures that matter most. "There's a strong feeling among many television critics that the image persists long after the narration is forgotten," says Howard Stringer, the executive vice president of CBS News. "On the daily story with the rush to edit, the pictures dominate, almost despite the narration. The White House -- and all great politicians -- understand that."

"If they actually give you sound and visuals of Ronald Reagan speaking on television," says Baker, "that can be a plus for us because he's so good -- even if the story line is negative."

So here, from a recent campaign day, is a look at the front line. For a relatively uncomplicated, one-day trip with three stops in Pennsylvania and West Virginia, and returning to Washington that night, the campaign spent $80,000 -- just on staging the events. CBS, excluding the salaries of the dozen people on the trip -- but including transportation, overtime, telephones, couriers and transmission and videotape costs -- had a budget of a little less than $20,000. Planning the Day

8:30 a.m. Zirinsky is on the White House press charter, handing her dozen charges her four-page "note," which is an excruciatingly detailed memo of the day's trip, listing where each camera crew and correspondent is to be where and when. There's a number for every airport, filing center and camera platform, most of them CBS phones she has ordered herself. On longer trips, like Reagan's final campaign swing, the note, says Stahl, "is the size of the Torah."

Zirinsky says she has an anxiety attack every morning of her life, and this morning she is in usual form as a walking No-Doz. When New York doesn't like one of her stories, she has been known to hang up the phone and cry. "It's a problem," she says. She would look naked without her walkie-talkie, which may as well be surgically attached to her hand. Campaign lore has it that she can't go for 30 seconds without using it, even if it means just saying hello to a correspondent a few seats away on the bus.

Today, she is preppily dressed in a blue and white striped cotton blouse, a blue skirt, white stockings, a strand of pearls, press tags, and, in her ear, a little wire attached to the radio on her belt that's tuned to the Secret Service channel. That way she can hear the president's comings and goings -- down to the second. "This business never lets you feel relaxed," she says, as if anybody could be relaxed while wired up like a Christmas tree. "One of my most comfortable moments is when Reagan is taking off -- for home. If he's taking off for somewhere else, it's still my responsibility. The bottom line here is: What if he gets shot?" Still, her job has taken her from Windsor Castle to China's Great Hall of the People. "Every so often, I'll think, 'I'm being paid to do this,' " she says. " 'Somebody's going to find out about this scam pretty soon.' "

As the producer for both Stahl and Plante, she has had to learn to deal with two of the strongest, most diametrically opposed personalities in television. Stahl is a cool professional on the air, but can become a frantic, obsessed perfectionist before a broadcast. Plante appears relaxed, on or off the air, but is every bit as intense. "Lesley is a little easier because I can accept her craziness," Zirinsky says. "With Plante, I may get a little more of a severe headache because I'm internalizing more. I'm manic and not everybody in the world is manic. He's laid back, and I don't want to drive him crazy. I've become extremely unstrung by run-ins with Lesley and Bill. But when it's over, it's over."

Now, as the plane starts descending toward the first stop of the day in Lancaster, Pa., Zirinsky packs up her gear and scours her notes. Neither she nor Plante is sure at this point what the day's story will be, but they've still got a few hours before they'll have to decide. Setting the Stage

The White House began planning this trip days ahead, particularly the second event on the steps of the graceful, white-columned Delaware County Courthouse in Media, Pa. Five days before, Bill Henkel, the chief of the White House advance office for presidential trips, had arrived to check out the site.

"It was a natural," he says. "It was a very classic setting, plus it dead-ended in front of the street, so you had a good crowd area. I saw the whole thing in a matter of 30 seconds."

He knew the networks would like it. "We spend a lot of time with the cameramen and photographers, asking, 'What did you think of that, how could we make it better?' " he says. "Susan wants a photographically interesting piece. I can do nothing to sway the editorial content, but I sure will do everything I can to make sure the pictures are conveying the story we want to get out."

He knew, too, that the crowd would most likely be enormous in an area dominated by what is locally referred to as the Delaware County War Board, one of the nation's oldest and most powerful Republican machines. Henkel, who used to develop marketing programs for Merrill Lynch, often figures out what kind of crowd he'd like to get to an event, then lures them with specialized mailings and offers of free shuttle buses and parking tickets. "This was just picking a good location," he says. "There was no magic to that one."

But there was one major snag: As masterful as the Reagan campaign had been through the fall, this trip came as they were encountering a real problem with their media coverage. Reagan's large crowds just weren't getting on the evening news, and seeing Walter Mondale's huge hordes on television every night was beginning to eat at the White House. "We asked why," says Baker, "and the correspondents and writers said they weren't able to see the crowds from where they were standing."

So the White House devised a clever plan:

They would take a group of cameramen as well as writers and correspondents up to the third floor of the courthouse, giving them a panoramic view of the crowd below, the kind of shot that dared you not to use it. Normally, the White House builds a scaffolding behind the president and then cuts a peephole in the backdrop so the cameras can get a view of the president facing the crowd.

But after talking to the network people, the White House realized that in the rush of the day, the correspondents and producers often don't see everything that's been shot. "It's obviously not enough to give them film coverage of the crowd," Baker says. "You have to have the correspondent there so it gets into the piece." Eyeing the Scenery

1 p.m., Pennsylvania. Zirinsky's day is bumping along. The first rally had been in the gym at Millersville University, where she made notes of a heckler who was dragged out by two Reagan supporters, then ran for the press bus, stepping in mud and coating her left loafer, as a campaign staffer yelled, "Let's roll it!" Once on the bus, she set up her mini-television monitor on the last seat next to the bathroom, and with a technician began looking at the videotape shot in the gym. She made notes of each scene and its time on her typewriter, giving the good shots one to five stars, as in "10:25:27 kid putting mouth over protester yelling*****"

Now, the bus is just about to arrive at the courthouse. ABC correspondent Mike Von Fremd wiggles past her into the bathroom with a brush and hair spray to get his hair under control. "I have to put on my hair," he says.

"Helmet to go," says Zirinsky, barely looking up from her screen.

Once at the courthouse, she heads out to the camera platform, pleased with the way it looks. She can't see much of the crowd of 13,000 jamming the street, but is glad that the White House has told her that both cameramen and network correspondents will be able to get an unusually good view from above.

Zirinsky notes the hecklers, climbs back on the bus, then screens the videotape shot just moments before. She sees the scene of the huge crowd at the courthouse and stops, impressed. "That's a great shot," she says, giving it a star in her notes and mentally reminding herself to get it on the air. (ABC used it, too; NBC didn't.)

The walkie-talkie crackles. It's Plante, who's in a helicopter on the way to the next event. "Reagan came over and talked to us," he reports. "He called our bluff, and we had nothing really to ask him."

"Sounds like he's afraid of being passed over on the evening news," says Zirinsky. On the Stump

Meanwhile, Jim Baker was pleased with the way the day was going. "We were using the stump speech and we had an insert," he recalls. "We were beginning to get more positive in our message. We were talking more about unity. We were trying to get the message across that the polls don't vote -- so go get out there and vote -- and also the idea of 'Give me a Congress I can work with.' " Paying Her Dues

Back on the plane toward Parkersburg, the last stop of the day, Plante and Zirinsky confer. They decide that the only new thing that Reagan has said is that his supporters should get out and vote -- and not trust the polls. Plante starts writing his narration and prepares to do his stand-up at the airport when they land. As he walks out on the tarmac, Zirinsky looks at him with a well-trained eye. "See, Plante was walking very leisurely," she says, "but now you'll notice his pace has quickened. He realizes he has to do a stand-up. But you'll never see him run. He doesn't want to appear that he's anxious."

Zirinsky has never been anything less than anxious. "I had the only parents in history who told me to stop studying so hard in high school," she says. She grew up in Lawrence, Long Island, the middle child of an industrial real estate developer. Her mother runs a psychiatric hospital that the family owns. Zirinsky went to American University, got a job answering phones at the CBS Washington Bureau once a week, and then, during her senior year and in the midst of Watergate, was promoted to typing the scripts for the "Evening News." "It was intoxicating," she says. "I was living in the dorm but going to work at CBS. I felt like I was a part of history." The night Nixon resigned, she noticed Walter Cronkite's script in the wastebasket. "I took it," she says.

In August 1974, she became a CBS researcher. Two years later when she was 24, she became the youngest associate producer there. Her title is now producer.

She was married in San Francisco's City Hall on the day after this year's Democratic National Convention to Joe Peyronnin, an "Evening News" senior producer in Washington. They met when both were associate producers, but he was promoted in 1982 and is now her boss. They had lived together since 1979. "It's very tough," she says, "but it's also like having your best friend be your boss. We have many public disagreements, but it's better than going home and letting it fester. It makes everybody else miserable, but we feel quite good about it. But sometimes, after a long day, when you just want to crawl into bed with somebody, there he is, saying, 'Hey, what was wrong with the bottom of your piece tonight? Plante looked really weird -- although I wasn't going to bring it up.' Then I start to scream loudly in the dark."

"I try to treat her like everyone else," says Peyronnin, "although occasionally I'll give her a hug and a kiss, and everyone will say, 'Yech.' When I first started, I would get mad at her and raise my voice, and then I'd notice people sneaking out of the office and closing the door. She also calls me an idiot and a jerk, which no one else who works for me does." And Finally, Done

That night, as Zirinsky's plane was heading back to Washington, a 23-year-old Reagan-Bush campaign worked named Tucker Eskew was carefully reviewing her day's work. As he sat at Reagan-Bush campaign headquarters at the foot of Capitol Hill, Eskew monitored all three network news shows and prepared the daily report that would be sent the next morning to the White House.

"Bill Plante had to choose between which mood best characterized the Reagan campaign -- caution or jubilation," Eskew wrote. " 'Beware complacency' was the president's message as he exhorted his backers to 'stop reading the polls' and plan to vote next Tuesday. Plante noted the president's efforts to spread his coattails."

Generally, the White House was happy, particularly with the pictures of the crowd. "If you noticed that night," says Baker, pleased, "there were good shots of all of the people."

At 8 p.m. Zirinsky's charter flight landed at National Airport. Despite the editing chaos at the high school, her day had been relatively easy. She was glad the White House hadn't scheduled any event too close to her deadline.

"We're talking simple logistics," she said. "The White House will look at something that's going to be over by 5:30 and say, 'Can you make this?' And you'll say, 'I'm not going to tell you what to do -- but we could sure use an extra hour.' And suddenly, the schedule will slip back. Let's be honest. Part of their job is to get these stories on the air.

"If a story fails to make a network because of a scheduling error -- why bother? Why are we here?"