Former WRC radio sports talk show host Daniel I. Snyder was convicted last night of operating an illegal sports bookmaking operation that got caught placing bets with FBI agents posing as bookies.

A jury found Snyder, 39, guilty of conspiracy and nine racketeering-related charges after deliberating for about three hours in U.S. District Court in Alexandria.

The trial was marked by unsubstantiated testimony that Snyder had inside information that referees were taking payoffs to fix professional basketball games.

Snyder, the pudgy former host of the program "Who's Gonna Win on Sunday," showed no emotion when the verdict was announced. Minutes after emerging from the courtroom, he said, "It's unbelievable. I'm just not a bookie and everyone knows it."

Judge D. Dortch Warriner, who presided over the four-day trial, set sentencing for April 22. Snyder could be sentenced to as long as 41 years in prison plus $90,000 in fines, according to prosecutor Karen Tandy.

Much of the trial focused on Snyder's loud personality as the jury was asked to decide whether he was the illegal small-time bookie the government claimed or a "sick . . . neurotic bettor" who the defense said was illegally entrapped as the result of an overzealous investigation.

"They threw out a net to haul in a whale and instead they pulled in a sardine," Judge Warriner observed at one point.

Snyder was arrested after a six-month FBI undercover investigation in which three agents and a middle-aged woman informant, named Mae (Kitty) Sullivan, posed as sports bookies or bet-takers. Operating out of an Arlington apartment equipped with two phones, from December 1978 until May 1979, they took "lay-off" bets from 10 other bookies in the Washington area, paid off winnings, and sometimes even demanded payments from other bookies who fell behind, according to court testimony.

The potentially most explosive revelation occurred when Sullivan, a 27-year gambling veteran, and another government witness testified that Snyder gave them in advance the correct victory margin, known as the "point spread" or "line," for eight professional basketball games that he claimed were fixed in February, March and April 1979.

Sullivan testified that Snyder told her referees made a fortune by taking payoffs for fouling out key players during games.

The National Basketball Association strongly denied the fixing allegations, saying its own investigation found them to be groundless..

Snyder, who took the stand in his own defense, labeled the fixing allegations "puffery" that he uttered to impress Sullivan. "Mae (Sullivan) would put me on and I would put her on constantly," he said.

Snyder also denied that he took bets from White House press secretary Jody Powell and other public officials -- claims Sullivan said he made to her. "I never talked to Jody Powell in my life," he said.