Summer TV doldrums have really set in, with lots of repeats on the schedule . . . and very little else. For many, this may be the right time to roll the TV set into the closet and use the comfortable recliner for reading instead of viewing. If you must watch, however . . . . SATURDAY British Open (ABC, 12 noon and Sunday, 10:30 a.m.): Live telecast of golf tournament from Royal St. George's Golf Club in Sandwich, England.
Cagney and Lacey (CBS, 9-11 p.m.): Repeat of the original made-for-TV movie which spawned the series that has become one of the best on TV. SUNDAY
Explorer (Cable -- Nickelodeon, 5-8 p.m.): New National Geographic show aimed at the whole family, featuring short travelogues and wildlife segments.
Evening at Pops (PBS, 8-9 p.m.): Boston's pop concert features flutist James Galway, jazzists Cleo Laine and John Dankworth. MONDAY
Heart of the Dragon (PBS, 8-9 p.m.): ``Trading'' episode of this superb series about the People's Republic of China examines recent attempts at free enterprise in China and in Chinese dealings with Western capitalism.
Smithsonian World (PBS, 9-10 p.m.): ``The Last Flower'' is repeat of fascinating program that featured the rescue of da Vinci's ``Last Supper'' from fading into oblivion.
Alive From Off-Center (PBS, 10-10:30 p.m.): Avant-garde television at its avant-gardest. You can be switched on by it or switch it off, but you won't be uninvolved. This program features a segment that satirizes TV programming and proves that nothing can satirize TV programming better than TV programming itself. TUESDAY
Skokie (CBS, 8:30-11 p.m.): Repeat of the poignant Danny Kaye special about Nazis who tried to march in Illinois . . . and Jews who were determined to stop them. WEDNESDAY
Born of Fire (PBS, 8-9 p.m.): Repeat of National Geographic stunner focusing on the science of plate tectonics, which explains how the earth's crust has evolved over the eons.
Witness for the Prosecution (CBS, 9-11 p.m.): Repeat of this surprisingly good remake, with Sir Ralph Richardson and ladylike Deborah Kerr.
World Professional Dance Championship (PBS, 9-10:30 p.m.): Repeat of a kind of vestigial rite -- Juliet Prowse hosts an old-fashioned dance competition featuring contestants from 24 countries and uncounted past decades.
Check local listings for all programs, especially those on PBS, where local option often results in varying days as well as times.