Without the sound of a gong or a pitch for Gillette Blue Blades, but with considerable advance fanfare, the Monday night fights were on the air. And just like that, they, and the Democratic National Convention from New York, were over, and another TV talk show had begun.

But the network news teams pressed bravely on. "Is this the end of Camelot," Morton Dean of CBS News asked Sargent Shriver. "Is this the death of old-time liberalism," Tom Pettit of NBC News asked Joseph Rauh. The questions get pretty drastic when the party appears to be over.

"Is that all there is," viewers may have asked themselves as, at 8:15, a roll-call vote became decisive against Edward M. Kennedy and his so-called "open" convention resolution, and the nomination of Jimmy Carter by the Democrats appeared to be a woebegone, foregone conclusion.

Then the last best hope for a thriller pretty much vanished shortly after 10 o'clock when Kennedy appeared in front of the network cameras to say "My name will not be placed in nomination" after all. It made a resounding pffft, and you could almost hear the faces of the network newsmen falling.

But while the steam rolled, the Democrats and the networks put on a highly engrossing nailbiter. On Sunday night's CBS News Convention Preview, correspondent and anchorapparent Dan Rather told Walter Cronkite the convention would be "an entertaining brawl with elements of farce." The preidiction was a safe one, and of course the networks contributed some of those farcical elements themselves.

But because the first few hours of the convention had their own sure-fire, built-in drama, nobody had to manufacture a story. The networks were able to relax their distraction resources and leave most of the canned featurettes in the can, at least until the voting was over and the postmortens had been posted.

The Democrats may have been rowdier and grungier, in their usual way, than the Republicans, but at least they were fighting among themselves. There seemed to be less conbat between the politicos and the networks over what kind of impression would be made on the allegedly all-powerful television screen.

If the first night of the convention found the Democrats in shaggy disarray compared to the tidily orchestrated Republicans, whose convention played largely like "The Big Show," the presence and influence of television was still anything but inconspicuous.

Sen. George McGovern noted in his part of the debate that "finally at a Democratic national convention I've gotten on in prime time," a reference to the fact that when he flukily won the Democratic nomination in 1972, the historic event was seen only by an audience of insomniacs and night watchmen, since it aired at 3 o'clock in the morning.

Ah, but what McGovern didn't know was that not every network had its cameras focused on him as he spoke last night. NBC was terribly busy with a floor report from Chris Wallace and a commercial for Snack Shapes, "new from Nabisco."

Indeed, one never quite knew what one network or the other would choose to ignore, so that the only way to see an approximately complete version was to watch all three networks at once. Edward Bennett Williams opened debate on the Kennedy resolution, but not on CBS or NBC, which picked him up later. NBC exhibited chronic fear of the podium and all but ignored such speakers as Gov. Hugh Carey of New York.

When it came time for Atlanta Mayor Maynard Jackson to speak, NBC was running a commercial for the Fruit of the Loom guys and ABC was screaming about its upcoming edition of "20/20," the pinball machine that thinks it's a TV program. CBS was the only network to carry Jackson's remarks from the beginning, but then was the first to forsake him in honor of commercials of Polaroid and the Bell System.

The most interviewed man of the evening was campaign chairman Robert Strauss, waxing alternately unctuous and cantankerous depending on God only knows what. But there were one or two moments of stunning poignance as well. The most memorable of these came during a post-vote interview with Williams by Jessica Savitch of NBC News. Williams was trying to keep up at least a slightly optimistic exterior, but as he spoke, an inspired NBC director cut to a shot of Kennedy supporters who had collapsed in each other arms, sobbing.

Cronkite proved invaluable in his old dependable way during the roll-call vote when he kept up a running commentary on the significance of the tally. But ABC News, which doesn't take many cakes, certainly took one for having the best printed display of vote tallies on the screen and was also the only network to superimpose indentifications of delegates and delegation chairmen.

Among the elements of farce was one occasion when ABC's Sander Vanocur was reporting from the California delegation. Vanocur's voice could be heard on ABC, but ironically enough, he could be seen only on NBC until the ABC Camera crew finally found him.

The most awkward interview of the evening ended before it began when Phil Jones of CBS News tried to question Robert F. Kennedy Jr., who was on the floor talking with delegates. Kennedy ignored Jones completely, consumed with signing autographs. Jones hastly threw it back to Walter in the booth.

As befits a man having the stature of a head of state, Cronkite was receiving guests in his imperial crow's nest above the hall. Jody Powell gave his first interview of the night to Cronkite in the booth, and didn't appear on NBC until 9 p.m. Vice President Walter Mondale dutifully showed up to be questioned by Walter and was told by Cronkite to stand by until after a commercial. Once excused, Mondale was free to go over to the NBC booth and did.

The award for best laid contingency plan that went nowhere goes to Cronkite and Rather who at 7:14 p.m. tried to get a rumor going about Kennedy withdrawing and Secretary of State Edmund Muskie being all set to jump in and grab the nomination. By 7:15 p.m., this fanciful notion was dead as a doornail.

As happened at the Republican canvention, John Chancellor and David Brinkley of NBC News brought out the best in each other. Once the vote was over, Brinkley said, "After all the talk during the day about slippage and leakage and movement, it turned out the slippage didn't slip, and the leakage didn't leak."

And after ascertaining that Rauh considered expiration of American liberalism to be an invention of the news media, Chancellor said, "I don't know anything that people don't like in politics that isn't the invention of the news media.'"

It seems very likely, however, that the news media are going to be doing a passle of inventin' in the three nights of the Democratic National Convention that remain.

NBC and CBS cameras were the very best at capturing colorful details like Mr. Peanut hats and Moose Antler and hats and other kinds of hats and such placards as "Open Bars, Not Conventions," and the double-take inducing "queens for Carter." But the sweetest sight of all for CBS News, where Cronkite is anchoring his last convention, was a woman delegate caught handlettering a sign during a boring speech period. The sign said, "There will never be another Walter Cronkite." We'll drink to that.