American technicians whose secret Iranian base for monitoring the Soviet Union was occupied by Iranian militiamen said today that in the lonely days leading to the takeover they felt abandoned by the U.S. government -- and at one point even considered walking across the Soviet border and turning themselves in.

About 20 civilians, who said they are employes of the U.S. Air Force, worked at the top secret Kabkan monitoring station near the northeastern Iranian city of Mashad. They were evacuated today from Tehran on an Air France flight to Paris after having been held captive for about a week by Iranian militia forces.

Interviewed on the plane, members of the group reluctantly described their harrowing experience after last month's revolutionary upheaval isolated them from the outside world. They said they were well treated by their captors and all eventually got out safely, although they had "anxious moments" while being held at gunpoint by successive rival armed groups.

The leader of the American team at the monitoring station said its loss was in his opinion a "critical" blow to SALT verification. He said the base was "vital" for the security of not only the dUnited States and its Western allies, but for Iran.

His comment reflected obvious pride in what he considered a difficult but important job in the isolated base. But it was unclear how broad a grasp he had on the relative value of the data his post relayed to Washington or how it fit into overall U.S. monitoring of Soviet activities.

The remote base, on a mountain 40 miles east of Mashad, contained sensitive electronic surveillance and monitoring equipment. It was primarily used to monitor Soviet communications and other indications of their missile research and development program.

The technicians, relaxing on the long flight to Paris after almost a week of tension, said they knew nothing about reports that one or two other U.S. listening posts near the Soviet border were wrecked or looted by Iranian gunment.

In Washington, State dDepartment spokesman Hodding Carter denied that Iranian guerrillas had taken over any U.S. facilities.

Confined to their mountain since October and unable to cummunicate easily with the American Embassy in Tehran since a leftist guerrilla attack against the embassy Feb. 14, the Americans at Kabkan became the victims of a mounting campaign by local employes of the base, one of the technicians said.

So intent was the feeling of having been abandoned and cut off that the Americans at one points considered trekking north across the border and giving themselves up to the Russians, he said.

"We kept hearing various reports that we were about to be attacked," he said. "At one point we thought we were the last Americans left in Iran. We felt abandoned and some of us thought of going over. We figured we would probably spend a few years in Soviet jails, but that would be better than being dead forever."

The trouble at the base started Feb. 23 when Iranian Air Force personnel guarding the post turned against the Americans, they said. The Iranian employes allied themselves with the Iranian "revolution," but their main demand was for severance pay, the technicians said.

After the dAmericans were held captive by the local airmen, a contingent of Islamic militiamen, evidently sent by Iran's new revolutionary government, arrived and took control of the base following brief exchanges of gunfire, they added.

The militiamen were meant to protect the Americans, but they also held them captive at the base until their release was arranged by the U.S. and Iranian governments, the Americans said. The Americans said they were flown to Tehran for the flight out of the country.

"We had no weapons, not even an airgun," one of the Americans said as they relaxed on the flight, drinks in hand. He said the team's "protectors" initially thought the Americans were heavily armed and that they intended to blow up the base rather than give it up to the revolutionaries.

On arrival in Paris, the Americans -- many of them with long hair and beards and dressed in heavy parkas -- were escorted away by U.S. Embassy officials to avoid newsmen waiting at Charles de Gaulle airport. Some of the dAmericans reportedly intended to fly home as soon as possible, but others were planning to tour Europe for several weeks first.