WORTH NOTING ON TV
* WEDNESDAY
In the Spotlight (PBS, 10-11 p.m.): You can call Mary Chapin Carpenter a country music singer-songwriter, but her directness and evocative power often transcend the form. She's won four consecutive Grammys for Best Female Country Performance and another for Country Album of the Year (''Stones in the Red'').
This edition of the noted music series shows Carpenter in a July 4 performance at Wolf Trap, near Washington, in her first United States TV special.
The show includes clips from Carpenter's 1995 world tour and other gigs, as well as interviews with the singer.
* THURSDAY
Hiroshima: Why the Bomb Was Dropped (ABC, 9:30-11 p.m.): The controversial nature of this subject is shown by the heated debate over an exhibit at the Smithsonian Institution that included the Enola Gay, the plane that dropped the atomic bomb on Hiroshima.
In this this ''ABC News'' special, Peter Jennings looks at the issue from several angles as the United States prepares to mark the 50th anniversary of the end of the Pacific war. How was the decision reached? Was it justified?
The production calls on an array of records - diaries, decoded diplomatic cables, intelligence reports - and offers interviews with historians. Not-so-well-known factors are discussed, such as the role President Truman's concern about the Soviet Union might have played in his decision to use the bomb and the possibility that Japan would have surrendered anyway.
* SATURDAY
The Sports Show (CBS, 2-4 p.m., EDT): Call it a match made in tennis heaven: Monica Seles, former top-ranked female player before being injured in a knife attack, returns to the court for the first time in more than two years.
Her opponent: the great Martina Navratilova, nine-time Wimbledon champion who only last year made it to the Wimbledon finals again, then retired - although many feel she can still beat all but a handful of the best players in the world.
They'll play at the Convention Center in Atlantic City, N.J.
Please check local listings for these programs.
