Edwin W. Pfeiffer, who has been vice president and general manager of Channel 9 since 1978, resigned yesterday . . .

Cecil I. Walker, acting president and chief executive officer of Gannett Television, named Ron Townsend, WDVM station manager the past eight years, to replace Pfeiffer . . .

Pfeiffer has been offered a chance to become an equity partner in KOVR-TV, the ABC affiliate in Sacramento, Calif., which is to be sold to Narragansett Capital of Providence, R.I. . . . Narragansett also owns a radio station in San Jose, Calif. . . .

When the deal is concluded, Pfeiffer will run the station, which, incidentally, has a three-year contract with the NBA Sacramento Kings, currently a popular item in northern California . . .

According to Gannett Television, Townsend will be the third black to be named a general manager of a television station in this country. Just two weeks ago, Johnathan Rodgers was named vice president and general manager of CBS-owned WBBM in Chicago. Tenicia Gregory heads WGPR in Detroit . . .

Pfeiffer came to Washington from Providence, where he had run WPRI, when the Evening News Association of Detroit swapped stations with the Post-Newsweek Stations, the latter taking over what is now WDIV in Detroit from ENA in 1978 . . .

Pfeiffer inherited a strong station, and under his stewardship the CBS affiliate has retained its lead in local news ratings while picking up several major journalism awards . . .

Earlier this year, Gannett completed its purchase of Evening News properties amid speculation that the media conglomerate, which owns eight TV stations and 15 radio stations, intends to make WDVM its flagship . . .

Townsend was in CBS management in New York for nine years before becoming business manager for program outreach at the Children's Television Workshop in New York in 1969. Four years later, he joined Channel 9 here . . .

Yesterday, Townsend said, "I'm excited, delighted and a bit humbled. There's a dedicated group of people here and with Gannett and its resources, we'll build on the rich tradition of Channel 9, I'm sure" . . .

Pfeiffer said yesterday that "with the advent of Gannett, I'm leaving the station in good hands. They've shown nothing but class, it's a tremendously strong company, they're people people" . . .

Pfeiffer, who said, "I'd like to see if I can be an entrepreneur," flies to Sacramento later this week to visit his investment but will return to WDVM to help Townsend make a smooth transition. No exact date for his final departure has been determined . . .

A spokesman for Gannett said yesterday that blacks hold 12.4 percent of the top four management positions throughout its TV and radio holdings . . .

Maybe it was the absence of a Cinderella team, a college from a major urban market, or a Big Name player, but the NCAA basketball championship ratings were a little down Monday night . . .

Louisville-Duke in the finals from Dallas averaged a 20.7 Nielsen rating and a 31 percent audience share on CBS . . . down from last year's Villanova-Georgetown thriller, which did a 23.3/33 . . .

Best basketball rating ever on TV -- college or professional -- is still the 1979 NCAA title game that featured Magic Johnson and Larry Bird for Michigan State and Indiana State. That one did a 24.1/38 . . .

Channel 50 was 13 minutes late getting on the air Monday but the rest of its first broadcast day went off without a hitch (WFTY is due to show up in the grid next door next week) . . .

The new family-oriented station is already on cable systems in Fairfax, Montgomery and Prince George's counties . . .

Which reminds us, Financial News Network fans . . .

Even though the reformatted Channel 50 is no longer carrying the service, you can still find it on Arlington Cable, Media General in Fairfax County; Cablevision of Fredericksburg; St. Charles Cable of Waldorf; and Metrovision of Prince George's County, according to FNN in New York . . .

One of Captain Airwaves' very favorite programs, "Japan Today," bid sayonara on Channel 56 Sunday . . . after the program's underwriters canceled out . . .

However, WNVC yesterday said those same underwriters are planning a new series called "Japan This Week" and the station is negotiating for it . . .

"Japan Today" offered a candid look at Japanese business practices mixed with segments on ordinary life in that fascinating country. And if one kept an eye peeled, almost every week the camera stopped to enjoy a scene -- a temple or village in the snow, a tree branch, a garden -- that suggested the style of the great printmaker Hiroshige . . .

Organizers of the "Comic Relief" weekend special to aid the homeless said yesterday that to date at least $2.466 million has been raised through ticket sales, sales of T-shirts and the like plus the telephone pledges. Not totaled yet: funds from the write-in pledges. In addition, a 90-minute version of the Home Box Office special will air later this month on HBO, at which time further funds are expected . . .

Channel 7 is revising its morning schedule . . .

Starting next Tuesday (April 8), "Hot Streak" will disappear from its 10:30 a.m. time slot, to be replaced by "Headline Chasers," which moves from 9:30 . . .

The half-hour version of "Lifestyles of the Rich and Famous" will move into the 9:30 time slot. The rest of the morning schedule remains the same . . .

"The CBS Evening News With Dan Rather" finished first last week with a 12.6 Nielsen rating and a 24 percent audience share, followed by "NBC Nightly News With Tom Brokaw" at 11.9/23 and "ABC World News Tonight With Peter Jennings," 10.9/21 . . .

TV Ratings

ABC thanks to the Academy Awards, finished in a tie with NBC for the week ending March 30 as both compiled 15.8 ratings and 26 percent audience shares . . .

CBS was third with a 14.2/24 . . .

NBC promptly issued a statement pointing out that 11.5 hours of its 22-hour primetime schedule were reruns . . .

Skipping through the Other 45, NBC's "Sound of Music" finished in a three-way tie for 26th with two new NBC sitcoms, "You Again?" and "Valerie" . . .

NBC's "Stingray" tied for 36th, the premiere of ABC's "Mr. Sunshine" was 44th and CBS' "Sin of Innocence" movie was 46th . . .

The premiere of ABC's "Joe Bash" tied for 49th, CBS' new "Fast Times" tied for 53rd and CBS' "Mary" continued to flounder in 58th . . .

For that matter, so did CBS' "Morningstar/Eveningstar" in 59th and CBS' "Foley Square" in 60th . . .

The Final and This Late in the Game Perhaps Fatal Five last week included ABC's "Benson" in 61st place, followed, in order, by ABC's "The Redd Foxx Show;" NBC's "Kissyfur" special; NBC's Smurf special; and ABC's "The Fourth Wise Man," which was unwisely booked against "The Cosby Show" last Thursday night . . .