A Peek at Peaks : Hills: The mountains surrounding the San Fernando Valley are populated with more than multimillion-dollar homes.

Not all the buildings dotting the mountaintops surrounding the San Fernando Valley are million-dollar homes. Where the houses with the magnificent views stop, radio antenna installations and microwave relay towers take over, punctuated here and there by an oil pipeline or the remains of old military bases.

The four mountain ranges that corral the Valley are natural assembly points for such complexes, especially the east-west running Santa Susana Mountains to the north and the Santa Monicas to the south, which separate the Valley from the Westside and Malibu. The Verdugo Mountains to the east and the Simi Hills to the west, are by comparison, more pristine. They are not as well-positioned for the majority of radio communications requirements.

Just north of the Simi Valley Freeway, on a small unmarked side road off De Soto Avenue, is Browns Canyon Road, a two-lane asphalt strip that meanders up the side of the Santa Susana Mountains, past privately owned ranches and grazing cattle, until it reaches a former U.S. Army anti-aircraft missile installation at the peak.

The domain of C Battery, 4th Battalion, 65th Air Defense Artillery from 1955 until its closing in 1972, the site was turned over to the city and remained vacant until 1977, when it became the home of the 75 members of the San Fernando Valley Service District of the California Conservation Corps.

The CCC, a state agency established in 1976, was created to teach 18- to 23-year-old recruits about the environment and how to help develop, maintain and protect it, said Paul Merryman, 52, its assistant district director. Among other duties, he said, CCC recruits plant trees, work in parks and fight forest fires.

Merryman said the former missile base is a perfect CCC site because it is not only close to the area the corps wants to serve, but the 16 buildings on the 34-acre site are self-supporting. Dormitories, a dining hall and a water and waste system were all left behind when the Army removed the Nike Hercules anti-aircraft missiles and radar equipment.

Just east is Oat Mountain, where antennas and microwave dishes supported by radio equipment are housed in structures ranging from small shacks to multistory buildings. Almost every communications company in the Valley operates through Oat Mountain, he said.

“Everybody who uses a two-way radio is up here,” said Walt Getze, 46, a supervisor at Southern California Gas Company’s Aliso Canyon storage facility above Porter Ranch.

“From communications companies to tow-truck drivers, contractors and delivery services, you name it, they’re here,” he said, taking in the view: the entire Valley, downtown, Magic Mountain, the old Ridge Route and Newhall. As a small covey of quail a few feet away scooted by, he said, “And this is still real wilderness, too.”

AT&T; is the firm with the largest presence on Oat Mountain. “It was very carefully selected for the best signal,” said Manny Quijada, 41, an AT&T; communications technician. “It’s a matter of setting up the site so it’s in a position where there will be no interference or anything blocking the signal.”

To transmit and relay long-distance telephone calls, Quijada said, the calls are changed into radio waves and sent from one microwave relay station to another across the country, with Oat Mountain the first leap out of Los Angeles. “It’s basically in one ear and out the other,” he said. “We’re re-transmitting what we’re getting.”

Mark Sobel, 31, a two-way radio dealer leasing space from one of the antenna owners, puts it in even simpler terms.

“Radio works line-of-sight,” he said. “If I can see you, I can talk to you. And standing on Oat Mountain, you can see downtown. It’s perfect for radio transmissions.”

Geography controls access. Everyone traveling the winding dirt road to Oat Mountain has to travel through the gas company’s property: those who maintain the communication equipment, for example, or oil company employees working the many drilling rigs in the area. The road is closed to the public.

The Santa Monica Mountains that form the southern boundary of the Valley offer a few surprises--especially to unwary motorists. Mulholland Drive, for instance, is unpaved from Encino Hills Drive in Encino west to Canoga Avenue in Woodland Hills.

Although open to the public, this section is a nightmare of bumps, dips and potholes punctuated by rocks and loose dirt. Just below, paralleling the road, is a Union Oil pipeline that begins in Ventura, follows the Santa Monica Mountain ridge to Mandeville Canyon and then turns south to eventually hook up with the company’s Los Angeles refinery.

Mountain cyclist Mike Colabella, 27, of Sherman Oaks likes to ride up here because there are no cars to watch out for, he said.

“This stuff is like what I race on,” he said, pointing at the uneven, rock-strewn road. “I’m accustomed to it.” He rarely meets other people during his training rides. When he does, he said, he’s not always prepared for some of the questions he gets.

“The silliest thing was a gentleman who stopped his car to ask me how to get to the Ventura Freeway. Boy, was he lost!”

Bob Young, 68, and his wife, Norma, 60, of Encino occasionally come up here with Buffy, their golden retriever; they take a look around and remember when the Valley wasn’t as populated.

“When it’s wet, the road gets much worse,” said Bob Young, recalling the days when he motorcycled up here. Now he parks their car on one of the many roads that lead up to, but don’t connect with, Mulholland and walks the rest of the way.

Andy Jib, 18, of Canoga Park, still rides his motorcycle up. “It’s away from everything; it’s quiet, and it’s peaceful,” he said, adding that he wishes it were legal to take his motorcycle off-road.

Another former Army air defense artillery missile site is up here (a third site, shut down in 1969, was in the flatlands on Victory Boulevard near Haskell Avenue in Van Nuys).

Now designated San Vicente Mountain Park, the 10.23 acres once used by B Battery, 4th Battalion, 65th Air Defense Artillery, were deactivated by the Army in 1972. It has yet to be developed.

But unlike the site near Oat Mountain, little remains of this former missile installation except for a couple of radar tower foundations and a toppled guard gate, all heavily covered with graffiti and surrounded by fields of glittering glass shards from broken bottles.

“These undeveloped locations take a lot of abuse,” said Dick Ginevan, 50, chief parks supervisor for the Valley Region of Los Angeles City’s Recreation and Parks Department.

“People just go up there and raise hell and tear up the facilities. We supervise and maintain those that are developed, but on the undeveloped parks, people just seem to destroy them.”

Farther east in the Santa Monica Mountains, near Forest Lawn, is another building that houses city communications equipment. Sitting on Mt. Lee, the two-story, white frame structure with its 378-foot tower can be seen from the Ventura Freeway.

Built in the 1940s by the owner of a local television station, it served until Mt. Wilson became available for commercial broadcast antennas in the 1960s. When the station moved out, the city moved in.

And though the mountains surrounding the Valley no longer attract as many movie or television companies as they did decades ago, the area, especially near the CCC site above Browns Canyon, still sees occasional camera crews. On a recent day, a Canada Dry commercial and one for the California Lottery, featuring a horse-drawn chuck wagon, were being shot there.

“They also shot an episode of ‘Air Wolf’ here,” said CCC’s Merryman. “We were supposed to be a South American military compound, and they built a couple of guard shacks to blow up, using the facility in the background. It was a lot of fun.”