The members of both parties who have been saying since the election that the country needs an alternative to Reaganomics have a problem: they cannot figure out what it should be.

For all the talk since Nov. 2 about the need to create more jobs, there is no consensus on what should be done, and most of what is under discussion would have little short-run effect on the economy.

The great deterrent is the deficit. Spend more to stimulate the economy as has been done in the past and you drive up the deficit, already frighteningly large. Drive up the deficit and you may force up interest rates. Force up interest rates and you may choke off the recovery that is your goal.

Assorted Democrats have proposed new jobs and housing programs. But they have been careful to say they would pay for these by cutting back elsewhere in the budget, principally on defense, or by increasing taxes. They would thus be taking back with one hand what they were giving with the other. They would not increase government stimulus of the economy, just change the mix of government programs.

That is also the most that President Reagan apparently intends to do. He is said to have no intention of offering any new jobs program beyond possibly a highway and bridge repair plan that would be financed by a higher gasoline tax. That plan, his chief economic adviser, Martin Feldstein, said would have a "very small . . . net" impact on total employment.

"We can't resolve the problems and really do what is right for the unemployed unless we make the economy sound, expand the economy and thus create the jobs that we must have," Reagan said at a press conference last week. Past efforts at government job creation cost $66 billion and "got us nothing but an increase in unemployment," he declared.

However, the administration is aiming to hold economic growth to no more than 4 percent a year once a recovery from the recession begins, Feldstein said. That would mean the unemployment rate, now 10.4 percent and rising, would fall by only about half a percentage point a year, he said.

At that rate, it would take seven to eight years to move unemployment down to 6.5 percent, a level many economists, including Feldstein, now regard as the lowest level consistent with an inflation rate that is not accelerating.

House Democratic leaders are drafting a jobs program they hope to pass during the lame-duck session that begins Nov. 29. But party sources on Capitol Hill acknowledge there is little hope of action that quickly without the president on their side, which he is not, except possibly for the road building and gasoline tax plan.

There is also considerable skepticism among members of both parties that an emergency, quick-fix jobs program would work as intended. "If we pass a bill in a three-week session, it's bound to be a bad bill," declared Rep. Bill Frenzel (R-Minn.), a moderate.

"I cannot see a major jobs program coming out of the lame duck," said House Budget Committee Chairman James R. Jones (D-Okla.).

Even liberal Democrats acknowledge there are problems with jobs programs of the kind they supported in the past.

"If you look at the EDA Economic Development Administration approach, a lot of the results didn't hit until unemployment came down. A lot of it was simply not job-producing," said one House Budget Committee liberal.

Jones agreed. "The decade of the '70s really did teach us that a massive jobs program is pro-cyclical and that there is a lot of waste," he said.

Nor is there total acceptance that new public works projects are the answer. "Basically there's nothing wrong with public works, but we can't just launch a big stopgap program without knowing its relationship to overall fiscal policy," warned Rep. James M. Shannon (D-Mass.), a member of the Ways and Means Committee.

Shannon, like many members of the House and Senate, wants more of a pay-as-you-go approach, with cuts in planned defense spending increases and tax increases offsetting any new outlays for jobs programs.

A key Democratic aide added, "People aren't talking about inflation per se, but they're still talking a lot about deficits, which reflects concern over inflation . . . . By conventional Democratic standards, this the forthcoming House leadership plan is relatively modest. In the past, a tax cut has been the engine of Democratic stimulus plans, but now all the talk is about tax increases" because of the deficits.

Indeed, most of the Democratic proposals, like those offered last week after a request from the House leadership by Rep. Henry S. Reuss (D-Wis.), chairman of the Joint Economic Committee, involve distinctly modest amounts of money with new spending more than offset by cuts in present programs or tax increases.

Reuss called for a $2 billion community renewal program under which people who had been out of work 15 of the previous 26 weeks would be employed on projects, such as road maintenance and public building repairs. He also proposed a youth conservation employment program, mortgage interest subsidies and slightly more money for regional development efforts, and sending a directive to the Federal Reserve that it seek to lower long-term interest rates, but only slightly.

Reuss also suggested holding annual defense spending increases to about 5 percent greater than inflation, which would save $1.6 billion from the level set in the 1983 congressional budget resolution. He would also cap the 1983 personal income tax cut of 10 percent so that no taxpayer got more than a $700 reduction.

Together, these proposals would add only $500 million to federal spending in 1983 and reduce it in later years. Including the tax increase would reduce the 1983 deficit by $500 million, and by roughly $9 billion in both 1984 and 1985, according to Congressional Budget Office estimates.

This package of changes would produce "many hundreds of thousands and perhaps a million jobs over the next year," Reuss maintained. "Remember, the interest rate changes are a very, very important part of this."

But congressional economists as well as those in the Reagan administration warned the net impact on jobs would be far smaller, perhaps negligible. "That kind of impact is just not plausible," said one Capitol Hill economist.

Asked about Reuss' prediction of the number of jobs his plan would create, adviser Feldstein observed: "That doesn't seem very likely."

The problem is that the jobs produced by spending on bridges or roads or public buildings or a youth conservation corps wages are matched by cuts in defense spending or tax increases. That reduces jobs in other areas, although there might be a net gain if a somewhat larger number of less well-paying jobs replace some of those held by more highly skilled workers in defense industries, one economist said.

A tax increase that is, in effect, fully spent by the government to pay wages and buy goods and services might also add marginally to employment. But the magnitudes involved in most of the proposals are so small relative to the size of the economy that their impact could be hard to find.

As Feldstein put it, "If you take a few billion out of food and clothing and put it into filling potholes, you will have better roads but you will have done a few billion dollars worth of damage [to employment] in food and clothing."

The same logic applies, he agreed, to the plan gaining favor in Congress and the administration to increase the federal fuel tax by 5 cents a gallon to fund a $5 billion-a-year program of road and bridge repairs and some mass transit spending. Employment would be shifted around and the nation would have better roads, but in terms of added jobs "you just don't get a lot out of it," he said.

Sen. Ernest F. Hollings (D-S.C.), ranking minority member of the Senate Budget Committee, who has been pushing a proposal to eliminate the 1983 personal income tax cut, reduce planned defense spending increases and freeze most domestic spending at current levels, said the jobs bill pushed by House Democrats before the recent election was "total eyewash. It did nothing."

The best jobs bill, Hollings said, would be to "get these deficits down so industry could reinvest once more . . . . That's the best jobs bill I can think of."

On the House side, Chairman Jones expressed similar thoughts. "I think there will have to be some sort of revenue bill next year. When you look at the options and the size of the deficit, you know you will not whittle it in half by cutting defense. You will not whittle it in half by cutting defense and entitlements. There is nothing left except to tackle the revenue side. It's either that or admit you are not going to get the deficit under control."

Jones said he does not expect congressional Democrats to be united in their approach either in the lame-duck session or next year. But unlike the last two years, he said, the Republicans won't be united, either. "Nineteen eighty-three may be one of the big crap shoots," he declared. "We don't know how the coalitions will line up. It will be a pivotal year."

Jones' Senate Budget counterpart, Sen. Pete V. Domenici (R-N.M.), is also determined to reduce the size of future budget deficits. At the same time, committee sources said, Domenici is working on a large, long-term program on highways, bridges, dams, airports, mass transit facilities and water treatment plants.

The program could cost $50 billion over five years and could be financed by a gasoline tax increase and a fee on imported oil.

Senate Republican leaders have not agreed to back the plan, which probably will not be fully drafted before January. Said Domenici, "A multiyear program and to go ahead and start it sooner than we would otherwise do is absolutely in order."

A number of members in the House said they are also interested in a longer-term program, not just something that might or might not improve the situation in the short run.

Rep. Leon E. Panetta (D-Calif.) said, "There's a lot of interest in a comprehensive approach aimed not just at jobs but at overall productivity." Such a program would include help for exporting industries, more research and development money and greater education funding.

Rep. Timothy E. Wirth (D-Colo.), chairman of a House Democratic Caucus task force on long-term economic policy, has no objections to a quick shot of spending on so-called infrastructure projects -- roads, bridges and so on -- if they do not conflict with his longer-term goal of "investments dealing with reindustrialization and world trade, including aggressive pursuit of lower nontariff trade barriers and targeting of U.S. investments overseas."

But others say reindustrialization is not a policy, just a restatement of the problem. There is not yet a clear alternative to Reaganomics any more for the long run than there is for the short run.