The codefendant at Sen. Harrison A. Williams' bribery trial said hours after the scandel broke last year that the New Jersey Democrat "is an honorable man," that a titanium mining venture he and Williams took part in was legitimate, and that government agents had attempted to entrap them.

Alexander Feinberg, 72, made the comments in a Feb. 2, 1980, call from Joseph Sylvestri, which was being secretly recorded with Sylverstri's approval in an apparent attempt by the FBI to get Feinberg to incriminate himself. The call was placed from the U.S. attorney's office in Brooklyn. h

Feinberg spent most of today on the witness stand trying to explain away incriminating statements he had made in videotaped meetings with FBI undercover agents. His conversation with Sylvestri was clearly a bright spot for the defense.

Sylvestri was indicted but not tried in a separate Abscam case. He and Feinberg were apparently working on a casino financing deal in Atlantic City, but the details were not clear from today's testimony.

Rather than helping the government, Sylvestri's call to Feinberg seems to support the defense's contention that Feinberg thought the mining venture had been proper and that the government had tried to induce corrupt behavior.

For example, Sylvestri was told to ask Feinberg what he should do if agents questioned him. "Well, just tell 'em the truth, Joe," Feinberg answered.

"Just tell 'em the truth, whatever you do, you never have to worry when you tell the truth. 'Cause I know we did nothing wrong and I wanna tell the truth and I told the truth, too."

Feinberg had been questioned hours earlier by FBI agents at his Cherry Hill, N.J., home. He mentioned his shock at finding Mel Weinberg and Tony DeVito were actually FBI undercover agents. ". . . They induced everything. They, they suck ya into a lot of things, too. There's nothing wrong, I mean Pete [Williams' nickname] was not gonna do anything wrong for Christ's sake. You weren't doing anything wrong, I wasn't doing anything wrong."

Later Feinberg added: "But, Jesus Christ, you try to be honest and fair, and decent. Ya, and I, and they started jumping on the senator, and I said, 'Look, let me tell you something right now, the senator is an honorable man.' I'm under oath so I'm telling you that right now."

Feinberg and Williams are charged with conspiracy and birbery in a scheme where Williams allegedly promised to use his influence to get government contracts for titanium from the mine in return for a $100 million loan to a corporation developing the venture. Williams allegedly held a hidden interest in the mine.

Feinberg said he was terribly disappointed to learn the agents weren't representatives of a rich Arab sheik as they had claimed. "'Cause I thought that our answer to our problems financially were gonna be over, that this goddamn thing was gonna be a, they were gonna make a legitimate loan and we had a legitimate deal and this is b------- all throughout. Talk about entrapment, for Christ's sake, and the way that Mel used to talk, he was terrible."

Under questioning earlier in the day by his attorney, Harry C. Batchelder Jr., Feinberg attempted to counter the impact of his own videotaped statements, introduced by the prosecution.

For instance, he testified he was trying to "placate and appease" the sheik's representatives when he said the senator's interest in the mine could be hidden and the senator could help get government contracts. He said the senator always intended in the titanium mine after the promised $100 million loan actually materialized.

In a May 31, 1979, recording from a men's room in New York's Hotel Pierre, Feinberg said "he [Williams] has to file a disclosure. If he files a false disclosure he's guilty of perjury, and he won't do it."

Feinberg did acknowledge that he agreed several times that the senator's interest should be hidden. But he said the hiding of the interest was only temporary and he did so only to avoid bad publicity similar to that he had incurred several earlier when the senator's wife's interest in another business deal became a campaign issue.

When asked what he meant when saying the senator could "open the doors" for government contracts, Feinberg said he meant only that the senator might make phone calls to an agency to make appointments about contracts. "I'd been under a lot of pressure from Mr. Weinberg. When I said 'he try' [to get contracts],' that was a matter of pacifying appeasing." s

Feinberg said he made such appearently incriminating statements "to keep them at bay. I didn't want to rock the boat, I didn't want to destroy this thing."

At another point he testified he was only "boasting and bragging" when he said he and the senator had helped fix and deal with New Jersey's Casino Control Commission. "Just like a salesman, we were puffing, we were bragging."