How does the Polish intelligence organization recruit Americans to spy against the United States? In the well-documented case of radar expert William H. Bell in Los Angeles, the approach was very subtle - at first. In the fall of 1977 at a chance social meeting, Mr. Bell met Marian Zacharski, the west coast manager for a Polish machine tool company called Polamco.
The two men had a common interest in tennis and began playing regularly. Over a period of months they became close friends. Mr. Zacharski was interested in Bell's work. He asked to see some of it. The work was classified, but Zacharski was a friend. Soon, Zacharski wanted to see more, and he began talking of the possibility of Bell being hired by Polamco as a consultant.
In addition, Bell had had serious financial problems. Zacharski saw to it that they were resolved.
What Bell, an engineer with Hughes Aircraft, didn't know at the time was that Zacharski had long been identified by US intelligence agencies as a Polish intelligence officer.
For almost two years Bell had thought Polamco was an American company. And he told a 1982 Senate subcommittee that he thought Zacharski's efforts were intended simply to gain a competitive commercial advantage for Polamco in the American marketplace.
''Within the avionics industry, it is common practice for all companies to obtain the secrets of their competitors by the same technique Zacharski used with me,'' Bell said.
He added, ''Even as I went to Innsbruck, Austria, (for the first meeting with Polish agents) I was rationalizing and kidding myself that the persons I would meet were representatives of Polamco, that this was just the kind of industrial espionage that goes on all the time.''
It was not. That was made clear to him by the agents he met in Austria. Bell said that after he had turned over exposed film of classified documents and received his payment, the Polish agents ''took great care to describe where I lived and shopped in frightening detail. They also showed me pictures of my family - my wife, and my young boy. They told me that if anyone caused a problem they would be taken care of.''
Bell told the Senate subcommittee, ''My financial burdens, of course, were resolved overnight. However, I was afraid when I could not or would not deliver more classified documents I would be liquidated or, much worse, my family would be endangered.''
It was in part this concern that led Bell, after his arrest by FBI agents in 1981, to confess and provide evidence against Zacharski. He said he wanted the FBI to ''go after the entire operation and shut them all down.''
Bell pleaded guilty in Los Angeles in 1981 to charges of selling radar secrets - including the so-called quiet radar system for the B-1 and Stealth bombers - to the Poles. The information is believed to have subsequently been delivered to the Soviet Union. Bell received an eight-year sentence and Zacharski was sentenced to life in prison. There have been no other arrests in the case.
In his 1982 Senate testimony, Bell said that even after Zacharski's espionage conviction, Zacharski's wife continued to receive Polamco paychecks.
Sen. William V. Roth Jr. (R) of Delaware asked Bell: ''Do you consider Polamco a legitimate company doing business in this country or do you consider it simply as a guise for Soviet spy activities through their proxy?''
''My feeling from what I have seen is that both are true,'' Bell replied, adding, ''When I discovered absolutely for certain that (Polamco) was under the control of the Polish government and that they use it as a cover for their secret-service operations, there is no question in my mind what they are here for.''
When asked about the Zacharski case in a telephone interview, Polamco President Stanislaw Ziaja said, ''There wasn't an implication about our company - never.''
He added that according to company files there had been no payments to either Zacharski or his wife following Zacharski's conviction in 1981.
''If one person in the company is doing something illegal, you cannot blame the hundreds of other people who are doing things right,'' says George Skrzypczyk, president of Toolmex Corporation, a Polish firm based in Natick, Mass. He adds of Bell's charges, ''This guy is probably making up some story to justify his lack of ethics.''
Toolmex is in the process of taking over Polamco operations, Mr. Ziaja says. Both firms are owned in part by a Warsaw-based state trading firm called Metalexport. Ziaja, a Polish national who became president of Polamco in July 1983, has been a director of Toolmex since 1979, according to Massachusetts corporate records. Polamco, which two years ago had annual sales of machine tools estimated at about $30 million, is expecting 1983 sales of about $5 million to $6 million.
The decline has come in large part as a result of US economic sanctions administered against Poland to protest Warsaw's 1981 imposition of martial law.
Foreign-owned firms - including state-run firms from East Bloc nations - are free to operate in the US. They are regulated by the laws of the states in which they incorporate. According to the Poland's commercial office in New York City, there are 13 Polish companies doing business in the US with products including ham, golf carts, glassware, machine tools, and electronic equipment.
Such firms played a key role in boosting US-Polish trade in the 1970s. The boost came during the period of US-Soviet detente that eventually saw Polish exports to the US grow to about $500 million in the late 1970s. Polish exports have since declined to about $200 million in 1983.