The Senate enters the television age Monday with a six-week trial of gavel-to-gavel broadcasting that could lead to major changes in the way the institution operates.

Debate continues over whether the change will be good or bad: whether it will sharpen, enliven and elevate the proceedings, as its proponents hope, or destroy the character of the "world's greatest deliberative body," as its foes fear.

But few members expect the experiment to fail, and many believe that it could profoundly alter many of the institution's most celebrated peculiarities, including its slow pace, loose discipline and free-wheeling independence.

"It has the potential to really transform the Senate," said Sen. William L. Armstrong (R-Colo.), a proponent who said he thinks TV will improve debate and strengthen procedural safeguards against sloppy action. Others, while agreeing that it could transform the Senate, contend that it could lead to aimless grandstanding and an erosion of the Senate's long-standing role as the last resort for dissenting views.

After a review of the trial run, the Senate is to vote July 29 on whether to continue. Barring an unforeseen fiasco, it is expected to keep on broadcasting, permanently or perhaps for another trial period.

The Senate will make its TV debut with a lot of ceremony and a touch of class when it returns from its nearly two-week Memorial Day recess. At 2 p.m., robot cameras, operated by remote control from a sophisticated recording studio in the basement, will begin to record floor proceedings from start to finish for both live and delayed broadcast by public and commerical TV.

Most senators are expected to show up in ready-for-prime-time uniforms (dark blue suit, light blue shirt and red tie). There will be speeches about the wonders of television and a party for former majority leader Howard H. Baker Jr. (R-Tenn.), who pushed for televising the Senate when few others seemed to care.

The C-Span cable network, which will carry the Senate proceedings live on a new channel, will operate out of a room adjacent to the chamber, starting at noon with a two-hour preview.

In addition to gavel-to-gavel coverage by about 120 cable systems and some UHF channels, such as WNVC (Channel 56) in the Washington area, major networks are expected to carry some segments of debate, at least on major issues, such as tax revision. NBC (WRC-TV), for instance, plans to show some of the opening ceremonies on its evening news Monday and may broadcast a half-hour special Wednesday night on the tax debate, according to Robert McFarland, Washington bureau chief for NBC News.

The Senate's opening debate will be on extending higher education programs, a favorite election-year subject that will allow senators to exercise their vocal cordswithout much risk of an unseemly raising of voices. The decibel level may rise later in the week with opening debate on the tax bill and a vote, scheduled for Thursday, on whether to override President Reagan's veto of a measure blocking a weapons sale to Saudi Arabia.

Technicians will be ready with recordings of Mozart, Bach and Beethoven to help ease the tedium during the long lapses when the Senate goes into drawn-out quorum calls and is unable to do anything else.

The Senate, which rarely does anything with dispatch, has been warily circling the cameras for some time. Increasingly restive over the attention the House has enjoyed since it went on the air in 1979, the Senate began easing onto the airwaves with live radio broadcasts in March and closed-circuit TV inside the Capitol last month.

Most kinks were worked out during that period, including how to handle the glare of bald heads (hold your head up and look into the cameras).

But the Senate remains divided on the question of music to relieve the tedium of quorum calls, so experiments with both music and silence will continue. Unlikely to be repeated is the rousing rendition of Tchaikovsky's 1812 Overture that boomed out, cannons and all, during a quorum call in the closed-circuit trial period. "At least it wasn't during the Saudi arms debate," said a relieved Senate leadership aide.

The month on closed-circuit TV appeared to have little impact on the Senate's behavior, although political scientist Norman Ornstein, a congressional scholar at the American Enterprise Institute who observed the members closely, said he thought they seemed to rely less on coaching from aides during debate.

With full-scale broadcasting, Ornstein said he expects senators to reach the floor better prepared. "In the past," he said, "if you made an ass of yourself, who cared? Now it's a whole new picture, literally."