Sure, he remembers - of all people on earth, he should. He was filling teeth in his Silver Spring dentist's office on Nov. 22, 1963. The radio bulletin came from Dallas. "And then I went home and watched Tv for three days like the rest of the world."

But that wrenching weekend was only a brief bubble of passivity for Dr. Gerald Jay Steinberg. A few months later, this otherwise sane soul noticed an ad in the Sunday paper. A stamp dealer was trying to peddle some new African issues that bore F. Kennedy's face.

Steinberg was a lifelong stamp collector who had just sold his collection. "But I figured, why not?" he said.

And so it bagan - a collection of JFK memorabilia that has been certified by historical and fellow collectors as the largest in the world.

"You name it, I got it," says Jay Steinberg. "I collected Kennedy. It just started branching and branching and branching.If it was Kennedy, I had to have it."

But now he doesn't want it.

After 13 years of dinner plates that sports Jackie's face in four colors, after writing as many as 100 letters a night in search of a rare Kennedy piece, after "lots and lots" of dollars, Steinberg is trying to sell the whole ball of wax. Much of it may go to other collectors.

"I've lost interest," he explained. "I can't build a museum (once his dream) so there's no reason to have it.

"Eventually, I'll give what I can't sell to the Smithsonia or the Kennedy Library. But only if they display it well. I don't want it all to get buried and forgotten."

For now, there's little danger of that.

To walk into Steinberg's office is to confront a maze of Kennedy mementoes that fills two whole storerooms, some of his desk and most of the walls.

There on one wall, in a fram, is a pressed oak leaf that once grew on the tree in front of the Texas School Book Depository.

There in the front hall are two portraits and two needlepoint caricatures. The face is a little hard to recognize in a couple of them, but not the words: "Ask not what your country can do for you; ask what you can do for your country."

Your taste tuns to the ridiculous? Steinberg possesses a letter Mrs. Kennedy once wrote to a Washington department store, asking if they would please exchange six pairs of her husband's ribbed socks for six paits of unribbed.

Or perhaps the sublime? Steinberg owns all the photos and artifacts that used to hang in Kennedy's Senate office. Not to mention various texts of his inaugural address.

Steinberg does not know how many pieces he possesses, or how much he spent to amass them. But he claims his collection of about 600 JFK medals and medallions is still the world's largest. His Kennedy stamp collection fills a whole shelf. "About the only thing I don't have is a Kennedy beer mug," Steinberg says. "Never found one."

Oddly, this jackrabbit of a man has no favourite piece. "I just never had one. The least valuable is as important as the most valuable. Some of it's good nedy, so I had to have it."

In some cases, Steinberg admits it was a "disease," that it cost him gobs of money and time, that it was ahobby "where you couldn't really win. I could never sell it for what it's worth, even if I wanted to, which I don't."

He doesn't even revere Kennedy as a President, although he voted him.

"Johnson was probably the greatest President in the history of the country." Steinberg said, "until he ran afoul of the kiddies." Kennedy "never really did anything expect found the Peace Corps, and I think I was more upset when Roosevelt died."

Besides, Steinberg said kennedy mania "may be a dying issue, finally.

"After the assassination, it was just vast. American business, dascinated by the fact that this was the way to get rich quick, produced everthing you could basically imagine." Today, though, "most Kennedy societies have died a natural death. There's only one left in Ireland, of all places."

Steinberg says he would have been more Kennedy material if it were not for a business dispute four years ago.

He decided to open a Kennedy gallery in Georgetown in partnership with Aubrey Mayhew, a Tennessee businessman and fellow Kennedy collector who once bough the Book Depository for $650,000 at an auction.

Both men contributed thousands of pieces from their collections, Steinberg said. But the gallery folded, he said, and the two men quarelled over ownership of some of the items. The dispute crested. He says he has taken up tennis, and is considering a plunge into needlepoint.

"I'm going to miss it, oh, yest," he said of his hobby. "But I don't really want to collect anything any more. I'll be sad when it's gone. But I felt a lot worse when I sold my stamp collection."