It was the most remarkable sight since television began to cover Inaugurations - and they would not shut up.

They - Watler and Roger, John and David, and Tom and Jane, Barbara, Harry and Howard K - insisted on talking incessantly throughout the 30 minutes that it took President and Mrs. Carter and members of their family to walk from the Capitol to the White House.

Only ABC's Sam Donaldson, who should win every award that broadcasting has to offer, had toe sense and the taste, when called upon for comment, to say: "Tell him I have nothing to say."

I'm not suggesting that the people who continued to talk as the Carters walked down Pennsylvania Avenue should have taken a vow of silence. There were moments when approriate comment could and should have been made. But the talks was nonstop, worse even than what we have come to expect from most sports announcers.

Television has been in existence for more than a quarter of a century, but its reporters do not yet realize that it is primarily a visual medium that talk heightens, underlines or punctuates.

There was plenty of natural sound along the parade route and there was enough visual material for the story to tell itself with the aid of only brief and succinct commentary. Carter, who seems a genius when it comes to using television for dramatic visual advantage, no doubt understood the symbolism of what he and Mrs. Carter were doing. The three networks probably understood the significance of what he was doing, but they failed miserably in projecting to us an unluttered view.

Television is not radio. We do not need voices to paint verbal pictures. Yesterday, the pictures spoke eloquently for themselves, but how they had to struggle over the babble of people who are in television but who do not yet understand how it should be used.