Turner to Offer All-Cartoon Cable Channel : Television: Turner Broadcasting System’s plans could further dilute the networks’ role in providing children’s programming.

Less than two months after it bought the Hanna-Barbera animation studio, Turner Broadcasting System said Tuesday that it will offer a 24-hour cartoon channel on cable TV, beginning Oct. 1.

The new channel offers further evidence of both the splintering of the television audience and the big three broadcast networks’ weakening grip on young viewers.

The tentatively named Cartoon Channel will air cartoons from the Hanna-Barbera library. Turner, the Atlanta-based parent company of the CNN and TNT cable networks, bought Hanna-Barbera--creators of “The Flintstones” and “The Jetsons”--for $320 million late last year.

Turner officials have not approached cable operators about carrying the new channel, and they acknowledged that it could take a long time to become profitable.

“We have very realistic expectations,” said Terence F. McGuirk, executive vice president of Turner Broadcasting System. “The business plan is based on modest growth.”

With most local cable systems lacking the space to add channels, no major new cable network has been launched successfully since Turner began TNT nearly four years ago.

But Turner has a major advantage over other companies: Just over half its stock is owned by a group of cable operators that includes Tele-Communications Inc. and Time Warner, which together serve about a third of cable subscribers nationwide.

“Since TCI and Time Warner have significant ownership interests in Turner, there is a pretty decent chance that if the Cartoon Channel has good programming, then it will be carried by some of the major operators,” said Ben Bendre, a Salomon Bros. media analyst.

If so, the Cartoon Channel could further dilute the broadcast networks’ role in providing children’s programming.

Once the sole purveyors of high-budget animation, the networks today are taking a back seat to local TV stations and cable as the major outlets of cartoon shows. NBC recently announced that it was bowing out of the Saturday morning cartoon race. The syndication market now captures about half of the $400 million spent each year on advertising aimed at children.

While much of the television industry is mired in an advertising slump, the demand for ad time on children’s shows has proven remarkably stable--and has even grown.

“Over the last two years, the kids’ marketplace has been very tight,” said Jack Deitchman, senior vice president at Oglivey & Mather advertising agency in New York.

The reason: Record spending by toy companies and a surge in advertising by fast-food chains and other advertisers who believe that the path to parents’ pocketbooks is through their children have driven up the cost of commercial time on popular cartoon shows, he explained.

Even so, the broadcast networks can no longer afford the kind of high-budget animation that studios such as Warner Bros. and Disney are producing for Fox and the syndication marketplace. Both Fox and Disney are selling seven-day-a-week cartoon strips to local stations--drawing viewers from the network’s usual Saturday offerings.

Meanwhile, cable networks such as Nickelodeon and Turner’s own TBS and TNT are scheduling their own low-budget cartoon shows. Advertising time on them is less expensive than on the networks.

Turner officials said start-up costs for the Cartoon Channel would be comparatively minor, compared to the cost of buying Hanna-Barbera’s studio and program library. By starting now, the officials explained, Turner would have a leg up when local cable TV systems begin upgrading their channel capacity over the next 5 to 10 years.