Reagan calls deficits 'a necessary evil'

President Reagan, long a foe of federal deficits, declared they ''are a necessary evil in the real world'' - his most candid acknowledgment to date of America's budgetary woes.

Mr. Reagan made the comment in a speech to the Los Angeles County Board of Supervisors. Through the 1980 campaign Reagan assured audiences he would balance the budget in 1983. For a time, he even boasted it could be done in the current fiscal year.