A House-Senate conference committee agreed yesterday to raise the pay of House members by 15 percent and lift the pay cap for nearly 33,000 senior federal executives and civil servants by anywhere from 10 to 15 percent.

Senators, who wanted to avoid the political heat generated by a pay raise, insisted they be exempt from the raise, but be allowed to continue to make unlimited income from speeches and other outside activities. Several House members asserted last week that allowing unlimited honorariums for the senators produces a windfall for many of them--far more than they would get from a 15 percent pay hike.

The raises for House members -- their first since 1979 -- and for the senior federal employes will cost the government between $60 and $70 million. The agreement reached yesterday will raise the salary of House members from $60,662 to $69,800.

The raises still must pass both the Senate and House as part of the stop-gap funding measure called the continuing resolution. Proponents say passage may be helped by the fact that the explosive pay issue is now an integral part of the emergency funding measure that must be passed to keep the government running.

Although President Reagan has threatened to veto the funding measure, his objections are to a jobs program and not to the pay raise measure.

Under yesterday's agreement, the pay of the vice president and speaker of the House will rise from about $79,000 to about $91,000. Cabinet secretaries would go from more than $69,000 to about $80,000. Subcabinet officials and other lesser agency administrators would receive smaller raises, with the lowest level of those employes having a new pay cap of $63,800.

Federal judges who now make about $70,000 will receive raises of about 4 percent.

The 1,400 members of the Senior Executive Service, an elite corps of executive managers whose pay has been capped for the past year at $58,500, would receive raises of between $1,000 and $9,000, for a new pay ceiling of $67,200. Only SESers in levels 2 through 6 would receive the raises.

The bulk of the increase will go to civil servants in the GS15, step 7 level, through GS18, all of whom are now capped at $57,500. These employes will receive widely varying raises, with a new cap of $63,800-- an 11 percent increase over the current cap.

Although members of Congress have not increased their salaries since 1979, both the House and Senate passed measures last year that allowed them to increase their total income without voting directly on a pay hike.

The Senate last year tossed aside a $25,000 cap on the amount of outside income members could earn from honorariums, allowing them to make unlimited sums. The House doubled the amount its members could make from honorariums, raising the limit to $18,200 with a parliamentary maneuver so slick and swift that some members didn't even know what had happened.

Both bodies also gave themselves hefty tax breaks last year, which were later repealed under enormous public pressure.

The measures were viewed by many as "backdoor" ways to increase salary and further heated up the already explosive issue.

It was with that background that the House last week approved the 15 percent pay raise introduced by Rep. Vic Fazio (D-Calif.). The Senate, however, refused to go along.

The thorny issue was resolved yesterday when Sen. Ted Stevens (R-Alaska) said he had crafted a compromise in which the Senate would go along with the House pay raise, as long as senators would be exempt.

Rep. Jamie L. Whitten (D-Miss.) quickly noted that the "quid pro quo" in the deal was that senators would retain their right to unlimited honorariums.

"The Senate is actually getting much more of an increase than the House does," Whitten said.

One congressional aide later said, "The congressmen are worried that they'll take it on the chin for the pay raise when the Senate is actually getting more."

The House retained its 30 percent limit on outside income, which will allow members to make about $21,000 a year in honorariums. Most House members could not command higher amounts even if the limit were raised, while the senators, generally better known, can draw far larger sums.

During the conference, Sen. Mark O. Hatfield (R-Ore.) suggested that all the honorariums be put in a single pot and then equally divided.

That proposal was met with hoots of laughter from the assembled crowd.