Television evangelism has been shaken up this year in unprecedented fashion, and no one knows that better than Oral Roberts, the Tulsa-based granddaddy of TV preachers, and a relative newcomer from Los Angeles named Fred K. Price.

Roberts got the first hint of bad news -- and Price the good word -- with results of the Arbitron Ratings of their weekly syndicated television programs in May, two months after reports of sexual misconduct by former "PTL Club" host Jim Bakker made national news. Arbitron told Roberts that his weekly show, "Expect a Miracle," had lost 155,000 viewers since February, dropping from third to fourth place among religious broadcasts. While Roberts' fortunes were falling, Price's show in Los Angeles, "Ever-Increasing Faith," had picked up 72,000 viewers and jumped from 10th to seventh place.

This shakeup, which shows little sign of stopping, is marked in part by an erosion of public confidence in longtime TV ministers such as Roberts, religious broadcasting experts say. Donations to these ministries are declining, and their leaders, and in some cases the leaders' sons, are scrambling to remake their images into something more palatable to an audience that has more religious programming to choose from than ever, the experts say.

"Some of these ministries are getting older, plateauing out," said the Rev. Ben Armstrong, executive director of the National Association of Religious Broadcasters. "At the same time, there's a younger group coming in, trying new things. It's a dramatically changing scene."

Yet as the old guard scrambles, newer, independent ministers who have embraced TV since 1980 are not doing badly. They tend to spend less, ask less often for money and, in some cases, broadcast programs with a more secular flavor.

Jeffrey K. Hadden, University of Virginia sociologist, includes in this list of newcomers three of Arbitron's top 10: D. James Kennedy from Coral Ridge, Fla.; Kenneth Copeland of Fort Worth, and Price. Of the old guard, only the Rev. Billy Graham, who has no regular show but is on television 12 times a year with millions of viewers, appears to be doing well, according to a Washington Post examination of the ministries' financial statements and to Art Borden, president of the Evangelical Council on Financial Accountability, a watchdog group.

Events of the last nine months -- reports of Bakker's adultery, Oral Roberts' statement that he could be "called home" to God if he did not raise $8 million, even Marion G. (Pat) Robertson's announced presidential candidacy -- only speeded up a reorganization already under way, according to those who have studied the electronic church phenomenon.

Donation figures from these ministries, where available, tell much of the story. The amount of giving to Roberts' ministry dropped 40 percent through the summer; support for Jerry Falwell's fifth-ranked "Old Time Gospel Hour" as much as 60 percent through the summer; funds to 10th-ranked Pat Robertson's 700 Club about 32 percent as of Oct. 31.

Top-ranked Jimmy Swaggart reported running $7 million behind, or 5 percent, in May (later figures were unavailable). Even second-rated Robert H. Schuller -- whose "Hour of Power" service from the Crystal Cathedral in California avoids negative news -- reported that his contributions, ending Sept. 30, were down 3 percent from the previous September. (All rankings in this article come from the Arbitron Ratings Co., and include syndicated TV programs only.)

Some of the newer ministries, on the other hand, appear to be having a good year. Contributions to Kennedy's weekly televised church service, for example, from January through August, were 19 percent higher than in the same period one year before, according to John Helder, executive director of the TV ministry. Incoming mail, from which the ministry gets new donors, was up 18 percent, Helder said.

The Billy Graham Evangelistic Association got off to a slow start in 1987, but by this month contributions were running ahead of last year's by about 4 percent, according to spokesman Larry Ross. The experience of ministries such as Graham's prompts Art Borden, president of a watchdog group that monitors religious broadcasters, to say, "People want to keep on giving -- they just say, where will it be used properly?"

In response to falling revenue, the large ministries have laid off employes and cut back on airtime. The most recent of these cutbacks occurred this month, when Robertson's Christian Broadcasting Network said it was reducing its budget of about $170 million by $9 million -- partly by laying off 145 of its 1,259 employes.

CBN and the other big-name ministries have had troubles peculiar to this year to explain some of the declining contributions. Robertson's departure from CBN left a vacuum that even son Tim, who became cohost, could not fill. And Roberts got caught by his claims that God would "call him home" if he did not raise $8 million by March 31.

Swaggart and Falwell became involved in the PTL scandal. Swaggart was accused by Bakker of plotting to take over PTL after Bakker left -- an allegation that was never substantiated. Falwell took over the embattled PTL ministry for six months, a move he now says cost his own ministry donations.

But they also have struggled with a reality several years in the making -- the continued growth in the number of religious TV programs, up 4 percent this year to 1,105, resulting in fiercer competition for a limited pie.

"We've been aware of a change in giving patterns for several years," Mark DeMoss, Falwell's spokesman, said recently.

Contributions to Falwell's "Old Time Gospel Hour" declined each year from 1983 through 1986, but they have risen slightly this year because of a $5 million grant. CBN has experienced two years of falling revenue, according to news reports.

Giving to Schuller's ministry, whose board includes such power brokers as Amway President Richard De Vos, fell $4.5 million to $35 million in 1986, according to the Orange County (Calif.) Register newspaper. In March of that year, Schuller cut $5.9 million from his budget by dropping 12 television stations and two cable outlets, and his viewership figures started declining.

Viewership trends are difficult to gauge because neither the Arbitron nor A.C. Nielsen companies adequately measure the significant number of people who watch these preachers on cable rather than commercial television. According to Arbitron, seven of the top 10-rated preachers lost portions of their audience from July 1986 to July 1987, the latest survey for which figures are available. Only Price, Copeland and "The World Tomorrow," a program of the late Herbert W. Armstrong's Worldwide Church of God, picked up viewers in the survey. (Graham's crusades are not measured by Arbitron.)

Those three share a low-key appeal for money; either they do not ask during their programs and rely on their literature to make that appeal, or they limit the number of their on-air requests.

The big-name evangelists apparently do not agree, for they have not noticeably softened their appeals this year, according to Stephen M. Winzenburg, assistant communications professor at Florida Southern College. Winzenburg reported recently that over the summer, the major evangelists spent an average of 11 percent of their time raising money, about the same amount he had measured in a similar survey in 1980.

Winzenburg concluded that the way these preachers usually ask for money -- either making the viewer feel guilty or promising wealth and happiness in return for funds -- contributes to the public perception that they devote more than 11 percent of their program to fund raising.

In their fight for survival, some of the old-line televangelists have reverted to practices that worked for them in the past. Roberts, for example, did a series of programs on faith healing several months ago. Both Schuller and Falwell announced recently they will spend more time on the needs of their local congregations, returning to the roots that nourish the rest of their programs.

Almost all of the old guard also have added new programming and formats, often designed to appeal to younger viewers. For example, Falwell recently started a relaxed talk show called "The Pastor's Study" to accompany his long-running Sunday-morning church service, "Old Time Gospel Hour." CBN started a radio network and spiffed up its "700 Club" to resemble what one newsmagazine called a "Good Morning Christian America" show.

The pop-religious format does seem to be working for the newer kids on the block, who include Copeland -- known for his improvisations -- and Price, who energetically works the audience of his 15,000-member Crenshaw Christian Center, illustrating Bible stories with humor and practical advice. The only black evangelist among the top 10, Price spins a message that appeals to a racially mixed audience, and he has inspired even newer preachers on the West Coast, according to Hadden.