Ronald William Pelton, arrested this week in Annapolis on espionage charges, struggled financially for years before he allegedly decided to spy for the Soviets. In the months just before the FBI says Pelton made contact with a Soviet agent, matters went from bad to worse.

Pelton, his wife and four children had been living for almost four years in what one neighbor described as "abject poverty" in a rural section of Howard County.

They were waiting for a new home to be built that, while modest, would have been a dramatic improvement over the tiny rundown farmhouse next to it where the family resided.

Pelton had taken out a $21,000 loan to build the new house, on top of a $9,000 mortgage on his two acres of property, and he found himself falling behind on his monthly mortgage payments and his property taxes.

He had left his $24,500-a-year job at the National Security Agency at Fort Meade, where he had worked for 14 years.

After two years of construction, the two-story house was not even a third complete, but consisted basically of a windowless frame with insulation between the beams.

So in the fall of 1979, Pelton and his family packed up their belongings and moved to a rented house in Bowie, unable to come up with a few thousand dollars that, according to one lawyer involved in the ensuing property foreclosure, would have put them back on their feet.

A few months later, according to an FBI affidavit presented at Pelton's arraignment Monday, Pelton made contact with the Soviets and began passing extremely sensitive information about U.S. intelligence activities directed against the Soviets that he had gleaned from his tenure at the NSA, largest and most secret of U.S. intelligence agencies.

Pelton, 44, who had a top-secret clearance at the NSA, is scheduled for a bond hearing today in U.S. District Court in Baltimore.

The FBI said he has admitted to spying for the Soviets, but his attorney, Fred Warren Bennett, said such statements do not necessarily constitute confessions. Bennett declined to comment yesterday on Pelton's background.

Pelton grew up in Benton Harbor, a small town on the far western edge of Michigan. He graduated in the top quarter of his class at Benton Harbor High School, according to a school spokesman.

After graduation he joined the military, according to the spokesman. He was then hired by the NSA at age 24 in 1965.

By the late 1970s, despite his income as a communications specialist, the Peltons were living in the decrepit farmhouse at 15800 Carrs Mill Rd., near the small town of Lisbon.

"The guy was pretty destitute," said one of Pelton's closest neighbors in an area where homes are separated by vast stretches of farmland. "The house was a wreck. He bought a camper and I think they were sleeping in the camper most of the time."

Gene Cahill, a retired D.C. fireman who lived about a quarter of a mile from the Peltons, said he visited the Peltons' home a few months after the family moved out because he saw smoke from what turned out to be smoldering mattresses. He said he "nearly threw up" at the sorry conditions.

Cahill said the house, which burned down on a later date, had holes in the walls, no insulation, only a small plastic pipe for water and a wood-burning stove for heat.

By the time the property was put up for sale in 1980 the Peltons were six months behind in their mortgage payments and owed $420 in property taxes, according to Dale Magnusson, who bought the property, and his attorney, Malcolm Kane.

Pelton ignored the foreclosure proceedings, according to Kane, as well as demands from the health department that he clean up his property.

Thomas Ogle, director of technical services for the county Health Department, said "there was garbage and trash strewn everywhere." He said his office had twice ordered Pelton to clean up the property and was preparing to take him to court when Magnusson acquired the site.

The house under construction, sitting amid high weeds and overgrown blackberry bushes, also fueled complaints to the building department.

"It sat there and sat there and finally it became unsafe," said M. Robert Gemmill, chief of licensing and permits. "We issued an order to have it torn down and it was finally done in '81."

At their new home, a four-bedroom house at 12203 Maycheck La. in Bowie, the Peltons again drew complaints.

Dan Howard, a next-door neighbor, said, "My wife remembers the driveway being strewn with broken car parts."

As in Howard County, the Pelton family members kept to themselves, neighbors said. By 1983 they were living in Silver Spring, where Pelton was working at a landscaping firm, Custom Environmental Services.

An officer of the corporation, who asked not to be identified, said Pelton served as "a consultant" to the firm from the fall of 1983 until this September, when "we didn't need his services any longer."

She described him as "a very nice person" who gave no indication of "leading any kind of double life."

In the spring of this year, Pelton found a second job as president of Health and Fitness of Georgetown. He separated from his wife, Judith, in July or August, according to his attorney Bennett, and was soon seen with a woman named Ann whom Pelton identified to friends as his girlfriend.

Reached by telephone yesterday, the girlfriend refused to comment. "I've just been out walking for miles and miles," she said. "You don't understand. My man is gone. I got nothing. I got no money."

She said she would comment later but added, "I'm going to charge for it, though. It's going to cost. It's that simple."