More than 400 people, including ABC News president Roone Arledge and Sen. Edward M. Kennedy, attended funeral services yesterday in Towson, Md., for Catherine (Cassie) Mackin, who died Saturday after a 14-month battle with cancer . . .

The funeral mass for the ABC correspondent was attended by numerous other television personalities, including NBC anchors Tom Brokaw and Roger Mudd and ABC anchor Frank Reynolds . . .

Kennedy, Reynolds, ABC anchor David Brinkley and attorney Edward Bennett Williams were among the pallbearers . . .

Kennedy and others praised the 43-year-old Emmy Award-winning reporter, noting that she was the first female TV reporter to cover a national convention in 1972 . . .

"I will miss her as a friend," Kennedy said. "I had enormous respect for her professionalism. She cared deeply about her family, her station and her faith . . ."

Miss Mackin, a pioneer among women in TV news, broke into the business in 1969 with Channel 4 here, joined NBC News two years later and moved to ABC five years ago . . .

Never thought about this before . . . but Joe Dembo, vice president of CBS Radio News, has written to Larry Speakes, White House deputy press secretary . . . to complain that President Reagan's use of colorful graphics on his televised addresses is "confusing" to radio audiences around the country . . .

Dembo, whose own radio network has 400 affiliates, solved the problem Monday during the MX address by having an announcer describe the chart involved as the president spoke to the cameras . . . but he doesn't think that's a satisfactory solution . . .

Dembo called the practice "confusing and objectionable" and noted that CBS Washington bureau chief Jack Smith has previously brought the problem to the attention of the White House . . .

Note to loyal "M*A*S*H" fans . . .

Be advised that CBS in New York made a "late programming decision" on Monday, yet, to preempt "Private Benjamin" that night instead of sliding the entire Monday night schedule after President Reagan's speech . . . as announced by the network on Friday . . . and that's why Your Favorite showed up in its regular time slot, after all . . .

CBS affiliates themselves weren't notified of the change until 12:57 p.m. Monday . . . Channel 9 recorded 15 telephone complaints, in part because (gulp) the TV Column had said "M*A*S*H" would air at 9:30 . . . Shape up, CBS! . . .

On the other hand, don't shape up too much, CBS . . . you've got NBC worried enough already . . .

So badly did CBS beat NBC last week in the prime-time Nielsens (see below) that "CBS Evening News," which airs in Twilight Time around the country, actually had a higher Nielsen average for the week than NBC's prime-time entertainment schedule . . .

For the week, "CBS Evening News" had a 14.7 Nielsen and a 25 percent audience share, compared with "ABC World News Tonight's" 12.3/21 and "NBC Nightly News' " 11.5/19 . . .

Meanwhile (see below) NBC did only a 13.8 in prime time . . .

David Hartman was absent from yesterday's "Good Morning America" and for a very good reason, indeed: the birth later yesterday of his fourth child (third son), 8 lbs., 2 oz.

No name yet, wife Maureen doing just fine . . .

Joining the Mutual Broadcasting System's press relations department on Monday will be Nancy Neubauer, formerly associate director of public information at the Public Broadcasting Service here . . .

Speaking of which, PBS president Larry Grossman has complained to Dick Ebersol, executive producer of NBC's "Saturday Night Live," about the Nov. 13 skit, complete with dancers who appeared in a "promo" for PBS claiming that "we're not stuffy anymore!". . .

(The skit ended with Big Bird standing in for the peacock in the NBC logo over the slogan "Proud as a Ph.D."). . .

In his letter to Ebersol (carbon copy to NBC chairman Grant Tinker) Grossman said that he knew "for a fact that none of the scantily clad young men and women . . . works for PBS" . . .

"Of course, PBS is still stuffy!" Grossman said. "Stuffiness is a PBS hallmark and we depend on it for most of our funding. Congress would not appropriate money to public TV if it were not impressed with our stuffiness" . . .

Grossman pointed out that "you'd certainly never catch the likes of Robin MacNeil, William Buckley or Alistair Cooke daring to wear a sweater on PBS the way Dan Rather does on CBS. They'd rather be seen naked than underdressed" . . .

"PBS," he continued, needlessly, "takes itself very seriously. We serve television for the humor impaired. That's why our nature programs with all those furry, feathery and finny animals; our avant garde drama; and our provocative documentaries get away with murder. On other networks it's considered sex and violence. On PBS it's high art."

Grossman demanded a retraction and an apology from "SNL," concluding, "We could also use some money."

(Grossman neglected to point out that PBS was referred to as the "Public Broadcasting System" on "SNL," even after 13 years as the "Service") . . .

This being the silly season, Ebersol was hiding in Connecticut and unavailable for comment yesterday. By the Way

We don't Do Radio ordinarily, but we're happy to report that despite the fact they didn't hit their goal of $10,000 . . . Howard University's WHUR-FM and the United Planning Organization raised $7,500 in cash and a truck-trailer full of canned food for their "Project Harvest" yesterday during a seven-hour live broadcast from 12th and F streets NW . . .

The annual project hopes to aid 20,000 of the city's needy this year . . . TV Ratingzzz

Following are the top 20 network prime-time shows last week, ranked according to the percentage of the nation's 83.3 million TV households that watched, as measured by the A.C. Nielsen Co. A share represents the percentage of actual sets-in-use tuned to a particular program when it aired. [TABLE OMITTED]

CBS really went out and did it to the opposition last week . . . winning every night except ABC's Saturday and taking a big lead in both the season and November sweeps ratings race . . .

CBS had a 20.5 Nielsen average and a 32 percent audience share for the week ending Nov. 21, compared with ABC's 17/27 and NBC's 13.8/22 . . .

Skipping very quickly down the list of 70 programs rated last week . . . NBC did have one piece of good news as its "Knight Rider" was ranked 30th, the best yet . . .

ABC's movie, "I Desire," tied for 35th, and the free-TV premiere of "Dressed to Kill" on NBC could only tie for 57th . . .

In the Final and Potentially Fatal Five last week, in order, were "NBC Sports Ringside," 66th; followed by that network's "St. Elsewhere" and "Gavilan"; and ABC's "Quest" and "Greatest American Hero" . . .