The Carter administration continued its campaign against a constitutional amendment to balanced the budget yesterday as Charles L. Schultze, chairman of the council of Economic advisers, told a House subcommittee such an amendment would have turned the 1974-75 recession into "the first real depression since the 1930s."

If a balanced budget requirement was in place 1974 "huge expenditures cuts would have been required and . . . unemployment would have skyrocketed," Schultz saaid.

He said estimates made from three econometric models showed the gross national product would have dropped 12 percent below the 1973 level, unemployment in 1975 would have risen to 12 percent and spending cuts of $50 billion in fiscal '75 and $100 billion in fiscal '76 would have been necessary.

Schultze's testimony before the House Judiciary Committee was part of a stepped-up campaign by the White House to head off the balanced budget drive which has now been endorsed in some form by 29 states. President Carter has already sent a letter to the Ohio state legislature asking them not to endorse such a proposal.

Freezing "a particular economic policy that may happen to fit the needs of the moment" into the Constitution makes as much sense as writing into the Constitution "a 55 mile-per-hour speed limit law, a 65-degree thermostat setting, a value-added tax or a prohibition on alcohol," Schultze said.

Schultze declined to eendorse passage of any law, constitutional or otherwise, requiring a balanced budget.

But schultze said congress has in place a budget process that would allow it to balance the budget right now if Congress had the will. Though the budget act could be improved upon, no further laws were needed, he said.

Despite what Judiciary Committee Chairman Peter Rodino (D-N.J.) called "the ballyhoo" over a balanced budget, no more than 25 people were in the committee room for Schultze's testimony, andonly slightly more than that attended a morning session at which former chariman of the Council of Econimic Advisers Alan Greenspan and James Dale Davidson, chairman of the National Taxpayers Union, testified.

Greenspan endorsed a constitutional amendment requiring a two-thirds vote of both houses to pass money bills. In the meantime Greenspan said he would support legislation doing the same thing to fill the five to seven-year gap that might be required to get approoval of a constitutional amendment.

Davidson endorsed a balanced budget amendment that would include a provision to set aside the requirement in times of emergencies.

He said nothing short of a constitutional amendment would stop Congress from voting for deficits which he said are in the political self-interest of members of Congress.