Redskin Coach George Allen apparently was more concerned about lack of depth at linebacker than he was about quarterback Billy Kilmer's back yesterday because he activated outside linebacker Joe Harris to his 45 man team.

Harris, an import from the Canadian Football League who was placed on waiver Tuesday, practiced with the Redskins during a 2 1/2 hour-closed workout.

Allen had been expected to activate quarterback Brian Dowling, then place him on the taxi squad. But with Chris Hanburger still in Arlington Hospital and Su O'Dell trying to recover from a sprained knee and ankle, Allen will keep Harris around for insurance, at least this week.

Dowling has stayed in the Washington area, however, and could be reactivated at any time through the sixth game of the regular season.

Allen apparently believes that Kilmer's sore back is not a major problem, and the club will to into Sunday's opener against the New York Giants with only two quarterbacks on the active roster.

"Billy had a good practice today," Allen said. "His back is much better. I don't really think it's anything. Some days you just get up in the morning and your back hurts."

Kilmer, who had declined comment Wednesday on his physical condition, said yesterday, "There's nothing wrong with me. I'm out there practicing. I'll play Sunday and there's no problem."

Trainer Bubba Tyer said Kilmer had spasms in his back Wednesday that caused him some discomfort. "Sometimes they last two or three days, sometimes less, and they go away," he said. "It's a lot better todays."

The Redskins' other main signal-caller is feeling better every day, about his new responsibilities on defense.

Ken Houston, who called defensive signals in two exhibitions after Hanburger was first hospitalized on Sept. 1, said yesterday he is approaching Sunday's season opener confident that he will have the Redskins in all the proper defenses at all the proper times.

Houston has done enough studying the last three weeks to earn some sort of advanced degree. The Redskins have 120 audibles and 70 defenses, "and I've got to know every one of them cold," he said.

"I go to extra meetings every day with the coaches and I'm doing a lot of work at home," Houston said. "I'm also getting a lot of help out on the field. Jake Scott is a real student of the game, and he makes suggestions between plays. And Harold McLinton is shifting the line, so it's one less thing I have to worry about.

"When I first started doing this, I never realized how much extra time is involved, how much preparation you have to go through. It's also a tremendous responsibility. If you make a bad call, well, I carry it with me for awhile. I don't even want to make a bad call in practice.

"But it's challenge for me. I'm not getting to sleep before 11:30 every night. I study films, I study the playbooks, I study other teams' tendencies, and I'm getting the hang of it. Coordinating the line play with the linebackers is the toughest part. But I feel like I'm getting more comfortable with it.

"All defenses are really designed to cover all situations, but some defenses do work better against certain formations. That's my responsiblity."

"We think Kenny's doing a fine job," said secondary coach Ralph Hawkins. "That one guy on this team you never have to worry about. He's conscientious, aleader, a real solid citizen.

"Whenever anyone ever asks me about the guy, I give'em the same answer. "Kenny Housten is a better person than he is a player, and I think he's a great player."

The first week of the season has been difficult for Houston aside from the extra work involved in calling signals. On Monday, two of his best friends on the team, Brig Owens and Jerry Smith, were cut. "It's not something you get over very quickly," he said.

"I don't really think you can fault anybody. I know it was a tough decision. They (the Redskins) have to look were young players and we beat somebody out of a job, and that's how you have to look at it.

"All three of us used to have dinner together before every game. Brig had a tremendous knowldege of the defenses, and we'd go over a lot of things. On the sidelines, he'd discusss what we were doing out there, and I'm going to miss that.

"In practice, I had to cover Jerry for as long as I've been here. He could still run a great pattern and he could still get open. You just hate to see those kind of guys leave.

"But if you stay in this game long enough, you know that sooner or later you'll be traded, you'll retire or you'll be cut. I've been fortunate. I'm playing my 11th year now, and I know it can't last much longer.

"I've told Ralph (Hawkins) that when he sees me slowing down a step, please tell me. I won't feel bad about it. I know next year could be the last year for me, and if it is . I won't leave the game bitter.

"I just know that football and friends don't mix. These things happen every year, and next year it could be me."

Allen said Hanburger may be released from the hospital over the weekend, but that he was still being treated with antiobiotics to fight off a postoperative infection . . . Running back of practice and said "I'm getting stronger every day.I feel great . . . Center Len Hauss returned to practice after missing a day with a sore knee. he is expected to start Sunday . . . Redskins still list Pat Fischer as doubtful for action in their injury report to the NFL, but the little corner back says he can play if Allen wants him to.