Bill Wendell's longstanding association with David Letterman ends today and his departure appears to be more bitter than sweet.

From Letterman's ill-fated daytime "The David Letterman Show" to his long "Late Night" stint at NBC to his current "Late Show" at CBS, Wendell has introduced "Daaaa-vid Letterman" for 15 years. Today, that era ends, as the voice behind the show retires.

Wendell's history as a broadcaster spans an even longer period, more than 40 years, including a stint with TV legend Ernie Kovacs.

Letterman declined to comment on Wendell or his departure. The show's executive producer, Robert Morton, said in a statement: "Bill has had an important role with us at NBC and at CBS. His voice will be missed."

Wendell--who says he hasn't spoken to Letterman since Christmas ("Our paths don't cross")--said just because he is retiring doesn't mean he'll stop working.

"Oh God, no!" he said by phone from the CBS editing room where he was putting the finishing touches on the day's announcements. (His other network jobs, including CBS promo spots and the introduction for the radio version of Letterman's Top 10 list, also end with today's retirement.)

"I haven't been out of work in more than 40 years for more than four months. If all goes well, I'll speak to a few people who want to talk to me about doing something else. I'm retiring," he said pointedly, "from this show."

Wendell's departure signals yet another hit for Letterman, who has seen some critics complain about a decline in the quality of his program and about his performance as host of this year's Oscars. For two of the last five weeks Jay Leno's "Tonight Show" has topped Letterman's in the national Nielsen ratings.

Wendell follows director Hal Gurnee and head writer Rob Burnett, other longtime associates who left earlier this year.

Wendell may have gotten the cold shoulder from the Letterman folks, but he's not left out in the cold. "I've done announcing outside the show and I have to call back folks who've expressed a desire to speak with me and we'll go from there," he said.

Wendell--who when asked his age, snidely responds, "I'm retirement age. How old are you?" then laughs vigorously (a reference book has his age at 71)--signaled his departure through his agent.

When word got out at CBS that Wendell wasn't renewing his contract, the response was, he said, "nothing. Letterman hasn't said anything to me at all about it."

Asked to describe his relationship with Letterman, Wendell said tersely: "I've never been to his house and he's never been to mine. OK?"

Wendell admitted, "It's a little strange between us," but pointed to many changes since the show moved to CBS two years ago this month. Wendell said he "just wasn't as involved in the show" at the new network. "We used to do skits, go over and talk with Letterman, all of that is gone. I have to leave it to others to say whether it's better or not."

Also not talking to Wendell are the show's producers, who--despite their comment to The Times--"haven't said a thing to me, either. Frankly, I don't think they care. They're worried about Westinghouse [buying CBS] and their ratings, not me."

Yet Wendell insisted, "That doesn't disturb me. It's no big deal. All I did was open the show with an announcement."

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Yet there's much more to Wendell. He can trace his broadcast history to television's earliest days. After two stints in the Army, and with a degree in speech from Fordham University, Wendell landed a job at WHAM radio in Rochester, N.Y., in 1947. After a time in Detroit, he moved to the DuMont TV network in 1952 and fronted three shows for a year. He also hosted "Mr. Adventure," a cowboy show. "Yes, it was embarrassing," he said. But at DuMont he met the brilliant Ernie Kovacs. Wendell became the comedian's right-hand man for his NBC prime-time comedy-variety show "The Ernie Kovacs Show."

But when Hollywood called Kovacs, Wendell remained in New York, hosting and announcing a series of shows.

One of his favorite jobs was a 1969-76 stint with Garry Moore on a syndicated version of "To Tell the Truth." Then Wendell's sepulchral tones resonated through various shows at NBC, eventually landing him at Letterman's morning show.

A few days before his final show with Letterman, Wendell reflected, "I look back on the days at NBC very fondly. . . It was really more confusion than anything else that I [didn't take a counteroffer from NBC and] decided to go with CBS and Letterman. There it is.

"There were friends I had at NBC, they're still there. I felt very badly that I didn't go with them, and stay at NBC."

As to his replacement, Wendell says, "I don't know and I don't care, but one gal told me that they're auditioning people every day. That's heartwarming."

William J Wenzel