WKRP in Cincinnati/Awesome

With his quiet, folksy personality intact and armed only with the lyrics to John Lennon's "Imagine", Arthur Carlson managed to reveal the hypocrisy of Richard Paul's anti-rock televangelist. Dr. Bob, a Jerry Falwell clone, was trying to strong-arm the station into playing no songs other than the ones on his religious-right organization's approved list. Dr. Bob boasted that his organization was made of millions of people who could boycott the station. Arthur Carlson read him the lyrics to John Lennon's "Imagine," asking if it would be added to the Blacklist or not.

Dr. Bob: The idea is man-centered, not God-centered. Man is an animal. The Bible tells us to put our reliance in God, not in our fellow mortals. Arthur, this song says there's no heaven.
Carlson: Ah. No, it says just imagine there's no heaven.
Dr. Bob: That's blasphemy.
Carlson: On the list or not?
Dr. Bob: I have no choice but to say on.
Carlson: That decision was made by one man.

- Earlier in the episode, Johnny warning of the slippery slope of letting these kind of people getting their way.

They sit there listening to the song, slower and slower, until, 'Ah, I heard a dirty word!'

The entire "Turkeys Away" episode. Fan reaction to that was so overwhelming that it convinced the network to keep the show - which was struggling in the ratings - on the air. There's a reason "Turkeys Away" was voted the greatest episode of any show, in any genre, ever broadcast in the history of television.
Bailey in a first season episode telling Herb after an episode of beratement to SHUT UP.
The episode where an old friend of Andy's comes calling... revealing that he'd been hired by Mrs. Carlson to review the station's performance without Andy's knowledge. Said friend also hints that Andy could skate on the "bad things" he's already figured about WKRP if Andy would buy his packaged-programming deal. Andy, betrayed, heads back to the station and convinces everyone there to act completely opposite of how they normally act (including Les). It works: Mrs. Carlson can't believe a word of the review... and compliments Andy on pulling it off.
Les, of all people, reveals his sure-fire pick-up line: "Hello. I'm incredibly wealthy." It even works on Jennifer.
What's considered the show's finale: Mrs. Carlson arbitrarily decides to switch to an all-news format just as the station is showing a profit. Johnny, of all people, figures out what's going on: Mrs. Carlson never intended for the station to be a success, merely a failed tax write-off. He confronts her about it, pointing out that she promised her own son that he would be the manager of the top radio station in the market. Confronted with that, Mrs. Carlson relents just as Carlson shows up to insist she keep WKRP the way it is.
In "Venus and the Man", in a tour-de-force performance by Tim Reid, Venus confronts a high-school drop-out who was running with a street gang and reached out to him by taking on the challenge of teaching him the structure of the atom in two minutes, framing the lesson in street-gang politics to make it stick. A rare Aesop episode that worked without being overly sentimental.