The Senate today will take up a Pentagon money bill that would give President Carter $5.8 billion more than he wants for defense. Neither the sponsoring senators nor the Pentagon is very happy about it. The president certainly is not.

The reason is that the bill -- providing $51.9 billion for research and weaponry, with another $948 million on top of that for military pay and educational benefits -- is largely a product of frustration. Many of the big weapons authorized in it are desperation choices, not the best money can buy.

The Senate Armed Services Committee, reflecting the same impatience that helped propel an equally generous procurement bill through the House recently, serves notice in the bill that it is tired of waiting for the Pentagon to invent the better mouse-trap and is settling instead for lesser ones in reach.

Senate frustration is the driving force behind recommendations to spend more than $7 billion on a warmed-over bomber, take missiles out of the warehouse just to have something more lethal pointing at the Soviets, spend $600 million to bring World War II ships out of mothballs and cut the Army by two divisions, Afghanistan or not.

The proposals have been trotted out before, only to be knocked over by the force of logic. But in election year 1980 you must look as if you are doing something now to improve the military balance with the Soviet Union, instead of waiting for technology around the corner.

The procurrement bill covers only about one-third of the total defense budget because funds for running the militry and building its facilities are contained in separate legislation. But the procurement bill gives the lawmakers their first chance to show they want some weapons built in a hurry to combat the Soviet arms buildup.

The Senate Armed Services Committee proposal for getting a new strategic bomber in the sky is the most dramatic case. The chosen machine is the F111 fighter-bomber, called the TFX in the 1960s when Defense Secetary Robert S. McNamara forced it on the Air Force and Navy -- for a while. The Navy TFX is now gathering dust in a museum.

The Armed Services Committee is urging the Senate to apprrove $91 million as a down payment on a $7.2 billion program to stretch 155 F111s into long-range bombers.

Many supporting senators would rather have the more technologically advanced B1 long-range bomber that Carter canceled in 1977. But they figure something is better than nothing.

William J. Perry, Pentagon research chief, warns that this something could well turn out to be nothing. He predicts the Soviets will have a new, lethal air defense installed by the time the stretched F111 is ready to fly in the mid-1980s.

"So it is a very expensive proposal providing us with a very uncertain capability," says Perry of the stretched F111.

The House Armed Services Committee, like its Senate counterpart, also yielded to frustration and impatience. Although preferring the B1, the House settled for a lesser successor called Strategic Weapons Launcher, or Swill is any more worth buying than the stretched F111.

Whether the lawmakers are right or wrong about their bomber selections is debatable. What's not debatable is that the Pentagon has been promising Congress for almost 20 years to find a bomber worth producing. It never has.

In October 1961, McNamara refused to spend the extra millions Congress had voted to continue production of the B52 and speed development of the B70. hThe following March, President Kennedy walked House Chairman Carl Vinson (D-Ga.) around the White House garden to talk him out of a bill directing the Air Force to spend extra money on a reconnaissance version of the B70. Then, as now, the Pentagon promised to keep looking for the ideal bomber.

During this long search, the B52s have grown older than their pilots. "Build me a new bomber," pleaded one pilot in a recent letter to Sen. George McGovern (D-S.D.) in which he detailed mechanical problems on his old B52. McGovern, once the leading Senate opponent of the B1, is urging colleagues to approve money for a new bomber, preferably the stretched F111 the Pentagon and many law-makers consider a waste of money.

Once again, the Air Force has a bomber on the drawing board that looks better to some experts than anything Congress intends to buy this year. Called the Long Range Combat Aircraft, it would fly high and slow but could be made invisible to enemy radar through highly secret gadgetry. But Congress, tired of looking at futuristic drawings of weaponry, is insisting that the Pentagon start cutting metal on something now.

The same impatience drove the Senate Armed Services Committee to recommend deploying 100 more Minuteman III missiles to add to those at the ready in underground silos.

Pentagon leaders believe this is a bad idea, too. For one thing, they insist that the 100 Minuteman III missiles the committee wants to use are needed for testing purposes. For another, they argue that yanking Minuteman II missiles out of silos and replacing them with the more lethal Minuteman III does not combat the biggest threat of all: Soviet warheads destroying any missile that stands still in a silo. The MX missile in development would move around so it would be harder to hit.

Pentagon civilians also make an impressive argument against the Senate committee's proposal to spend $294 million to bring the battleship New Jersey out of mothballs and $304 million to reactivate the aircraft carrier Oriskany. They contend that the Navy cannot find enough skilled sailors to operate the newer ships already at sea, much less find boiler technicians and other petty officers to operate the old ships once out of mothballs. But the House approved the demothballing and the Senate may do likewise in the "do something" mood that dominates defense decisions this year.

President Carter opposes the bomber ideas as well as bringing the two ships out of mothballs. But, in his eagerness to keep sending signals of strength to the Soviet Union, he would be reluctant to veto a Pentagon money bill that authorized the unwanted weaponry. The lawmakers seem to sense this, and are emboldened.

This president's desire to send the right signals also has brought him in conflict with several senators he needs most on national security issues. John Stennis (D-Miss.) and Sam Nunn (D-Ga.), to name two, want to cut the Army by 25,000 troops to force it to emphasize quality over quantity. Only by recruiting a larger proportion of high school graduates in the future could the Army get back up to desired strength.

Carter and his allies counter that cutting the Army by two divisions right after the Soviets' Afghanistan invasion would send the world the wrong signal. Besides, they argue, a personnel nightmare would be created as Army planners tried to figure how many troops they had to work with in a given month.

Here again it was frustration with the Pentagon promising but not delivering that impelled the committee to take matters into its own hands, an initiative expected to be more vigorously challenged on the Senate floor today than the recommended "quick fixes" in weaponry.