"Thank God he's doing something," said Phillip Lewis, the father of an American hostage. "It's about four months too late."

"Jimmy Carter's out of his mind if he thinks that's going to improve anything," Alan Graves, the son of another hostage, said. "The way he's going right now, the next step is war."

President Carter's anouncement of new sanctions against Iran drew widely varying reactions from the hostages' families yesterday. Some applauded Carter's move. Others criticized it. Others voiced frustration and uncertainty.

Lewis, whose son is Marine Sgt. Paul E. Lewis, 22, was among those who praised Carter's move. But he also expressed lingering doubts. "I just hope he carries it out," said Lewis in a telephone interview from Homer, Ill.

Graves, whose father is embassy public affairs officer John e. Graves, 52, angrily criticized the president. Carter's announcement represents "another half-measure" that would "pay off the companies that got us in this damn mess to begin with," Graves said.

The Graves family, which lives in Reston, has previously urged a congressional investigation of past U.S. actions in Iran. Graves' payoff charge referred to Carter's plan to help clear the way for claims against Iranian assets.

Emotionally drained after their five-month ordeal, other hostages' relatives said they scarely knew how to respond to the latest move.

"We've reacted so many times," said Dorothy Hall of Little Falls, Minn., the mother of a hostage."It just gets more frustrating by the day." Her son is Army warrant officer Joseph M. Hall, 31.

Some relatives watched Carter's announcement on a television set at a State Department office and were given an official briefing afterward. Louisa Kennedy, the wife of a hostage, described the families' reactions as cautious.

"The president is doing the right thing and it's good for starters," said Kennedy, whose husband is economic and commercial officer Moorhead C. Kennedy Jr., 49. We're not sure how strong these measures are."

The hostages' relatives raised a number of questions about the new sanctions, Kennedy said. These included how many Iranian diplomats would be expelled and what steps would be taken to invalidate U.S. visas issued to Iranians.

"A lot of this is still undefined," said Kennedy, who is also the news media representative of FLAG (Family Liaison Action Group), an organization recently set up by hostages' relatives."It's going to shake down in the next few days."

For the Sickmann family in Krakow, Mo., Carter's announcement was overshadowed by an unexpected telephone call. Marine Sgt. Rodney V. Sickmann, 22, a hostage in Tehran, was permitted by the Iranian militants to phone his family yesterday morning.

"He's more homesick than anything else," said Sickmann's sister, Judy Ehlenbeck. "He broke down and started crying pretty hard."

Several hostages have been allowed to telephone their families in the United States since the embassy takeover Nov. 4. Sickmann phoned his mother once before -- on Dec. 13, according to his sister. For the Sickmann family, however, yesterday's brief call from Tehran was more reassuring than the president's later announcement of new sanctions.

Depite his tears at the end of the conversation, Sickmann seemed to be bearing up well, according to his sister. "He said, Don't worry about me. Take care of Mom and Dad," Ehlenbeck said. She said he told his family that the Iranian militants were "making life very pleasant -- as pleasant as possible under the circumstances.

"In fact, when I hang up, I'm going to play Ping Pong," she quoted him as saying.

Nevertheless, the Sickmann family also drew some encouragement from Carter's announcement. "It's about time the president and the Carter administration took some action," Ehlenbeck said. But she added that she believes Carter's move does not go far enough. "He should cut off medicine, food -- the whole bit."