For many Americans, the resurgence of mortgage interest rates this fall has once again made the purchase of a home an impossible dream. And there is little relief in sight.

The unpredictable seesaw movement of rates during the past year -- ranging from a low of 11 percent to a record high of 17 percent -- has caused confusion and anger among builders, buyers, lenders and Realtors.

"It's a nightmare," says Ken Kerin, chief economist for the National Association of Realtors. "Some people who qualified for loans a few weeks ago are now out in the cold.

"It's particularly bad if those people signed contracts to sell their homes and then suddenly found they were unqualified to buy a new one because of another interest rate boost. They're literally sitting on moving vans with their furniture and have no place to go."

Current buyers who do have sufficient income to qualify and do find available mortgage money would have to swallow a 14 percent interest rate in most sections of the country. They would pay $710.93 a month in principal and interest to obtain a $60,000, 30-year mortgage. An identical buyer would have paid $571.40 for the same loan in late July, which is $139.53 -- or 24 percent -- less than current conditions dictate.

Three of the sharpest mortgage rate jumps in history have occurred since October 1979, mainly because of the Federal Reserve Board's anti-inflation policies which use tight credit as a tool.

Many people who were ready to buy homes watched helplessly a year ago as rates rose in a matter of weeks to around 14 percent from 11 1/2 percent. The situation was aggravated earlier this year when interest rates shot up again -- this time to an average 17 percent -- in response to adjustments by the financial markets to expectations of continued higher rates of inflation.

Just as swiftly, rates tumbled in June and July -- in some cases back to 11 percent. Housing construction improved markedly and buyers started to shop around, hoping to take advantage of the lower rates.

They had to move fast. By the first week in August, rates were moving upward again and potential buyers started to retreat to the sidelines.

"There's definitely a psychological barrier in the 13-14 range," says Roger Graham, loan officer for the Northern Virginia Savings and Loan Association in the suburbs of Washington. "Activity was good in June and July. Now it's virtually nothing."

The movement of interest rates has frustrated builders, whose livelihood depends on willing buyers.

"It's incredible," says Michael Sumichrast, chief economist for the National Association of Home Builders. "We've had three major upward mortgage moves of at least 2 1/2 percentage points in 12 months. Normally, it takes two to five years for one increase of that size."

"We simply must get some stability in the mortgage market," he added Tuesday in a speech at the 1980 convention. "The way things have been this year, there is just no rational way for builders or buyers to make advance plans. You cannot sell homes with 14 percent mortgage rates. It's ridiculous."

He said the latest increase in mortgage rates had "already had an impact on sales."

"The bottom line of all this, in the short range, is less sales, less starts and a pretty cold winter. I'd be a fool to try to tell you you can have a good year when the mortgage rates are 14 percent plus," Sumichrast said.

He said the Federal Reserve Board's changing policies tightening credit and monetary supplies "for us simply spells disaster."

He blamed many of the building industry's problems on the federal budget deficit and out-of-line government spending.

He said the nation paid $30 billion more on interest rates alone on federal debts than it did on building single-family homes last year.

According to Sumichrast, 90 percent of the nation's builders reported "poor" sales last March. That figure improved to 50 percent in May and June. It climbed buack to 63 percent in early September and now is at 80 percent.

Sumichrast says builders have lowered their construction expectations by 132,000 units for this year and by another 150,000 units for 1981 solely because of the latest mortgage rate jump.