The two newest big-city daily newspapers are still coming out after about two months, and although their advertising content is alarmingly low by industry standards both the Philadelphia Journal and the New York Trib say they will be around for some time to come.

Publishers Pierre Peladeau of the Journal and Leonard Saffir of the Trib said in recent interviews that they were happy with the circulation figures of their papers and were confident that advertising would be picking up.

Newspaper industry analyst John Morton of John Muir & Co. said that both papers are apparently weak in advertising, but he gave the Journal a better chance for survival.

"The Journal is appealing to a market not traditionally served by newspapers," said Morton, "while the Trib is going after a market already pretty well served by The New York Times."

The Journal, a racy tabloid with a heavy concentration on sports and crime news that began publishing in early December is selling "around 60,000 a day," now, according to Peladeau.

That figure is up from about 40,000 a day only a few weeks ago. Much of the increase, according to Peladeau, has come because the paper finally received and deployed several hundred newsboxes. Previously, the news-paper could only purchased from vendors.

Peladeau says he will have to hit 80,000 circulation before he starts making money. He has cut down from three printing plants to two that print his paper on a job basis. But, he says, he expects to be profitable "in a matter of weeks."

When that haps, The Canadian publisher will decide on a start-up date for his second American news-paper, which he says will be in either Atlanta or Newark, N. J.

Peladeau is cheered by the performance of his parent company, Quebecor of Canada, an American Stock Exchange firm which last week announced that four quarter profits were up 75 percent over last year to almost $2 million. He publishes two major French language dailies and a string of weeklies in Canada.

The profit figures include the first month of operations of the Journal, which Peladeau said involved an $850,000 writeoff for starup costs.

The Canadian publisher said the Journal hit 65,000 circulation one day last week, and added that he has hired in the past week a new national advertising manager and his first full time overall advertising manager.

In New York, meanwhile, the Trib has added a printing plant - the third New Jersey shop that is printing the morning tabloid.

"We really didn't need to go to a third plant yet," said publisher Saffir office." But we want to have any bugs in an interview in his Third Avenue ironed out when the time comes that we have to use three plants."

Saffir says the Trib, which began printing on Jan. 9, is selling "around 200,000 copies a day" out of a press run of about 250,000 - "except for the bad snow days, when we only printed about 90,000."

But there may be good news on the horizon for the Trib. The real reason Saffir has started printing in three plants prematurely is to be ready for something that may happen at the end of March - a strike against New York's three other dailies.

Labor strifes in the pressroom over manning provisions have led many industry sources in New York to conclude that a strike of some sort is inevitable. Unlike those papers, the Trib has a non-union shop in New York, although it is printed by union printers in New Jersey.

Since the other three dailies account for an estimated 3.3 million in daily circulation, a prolonged strike could give the Trib financial windfall that might make the difference between success and failure in the long run.

The Trib, a conservative (some say boring), daily mimick of the news magazine format, has been emphasizing news of the communicative industry - the only area in which its coverage excells over that of the other New York dailies.

Last week, for example, the Trib lead story concerned the Washington Post scoop of the New York Times on the Haldeman book. The lead story was a media story about the New York Times reaction to being scooped, and purported details of how the caper was carried off by the Post.

"That's the best front page they've ever had," said Sam Roberts, city editor of the rival Daily News. "They finally wrote a story for their audience."

Roberts and others at New York's other dailies have been critical of the Trib's general news coverage as "dry." But they hasten to add that it is written, in many ways, for people in the communications business - which is a major industry in New York. "It just seems like a good idea for them to go after media stories," said a New York Times reporter, "then I'll have a reason to buy it, and so will everyone in this business and on Madison Avenue. That should account for about 200,000 readers alone."

Saffir, for the first time, revealed who the major investors in the Trib are. Included from the begining were Ray Donovan, a New Jersey hotel builder who is a friend of Saffir; Robert Allen, son of Charles Allen of Allen & Co., David Faskin of San Francisco; Charles Carvin, of Carvin Industries in Florida, which manufactures seat belts: and Frank Augsbury of Ogdensburg, N. Y., who owns the Hall Shipping Co.