For armchair fans of the Washington Capitals, the season ends tonight. The Capitals' meeting with the New York Islanders at Nassau Coliseum will be televised by WTOP-TV-9 at 8 p.m. and it is the final telecast scheduled this season.

It is probably the last time the Capitals will appear on Channel 9, since the three-year television contract is expiring and WTOP has shown little interest in a renewal. At least, the station will go out in style. Tonight's game is one of the few to be shown in its entirety.

Dough Patey won't be watching it, either on TV or from his recent habitat in the press box. The 20-year-old right wing was shipped to Dayton of the International League yesterday. In 38 games as a Capital, many in a most limited role, Patey collected only three goals and one assist.

Still, it was an accomplishment just to stick around that long for a man who was both the NHL's youngest player and a lightly regarded fifth-round draftee.

"If he goes down and works as hard as he did here, he'll be back," said general manager Max McNab. "He learned an awful lot, but he needs more work. He didn't hurt us and in another year we think he'll help us."

Patey's principal difficulty was in the shooting department. Often set up for good shots, he usually missed the net or fired directly at the goalie. Coach Tom McVie after frequently admonishing him in practice to pick the corners, eventually gave the youngster less playing time.

While Patey headed for Dayton right wing, Bill Riley was striving mightly to avoid a similar fate. Riley, technically a hockey amateur, is with the Capitals on a 10-game trial. He has already played seven games and must impress tonight, in Sunday's Capital Centre rematch with the Islanders and in Tuesday's home game with Montreal, if he is to earn a pro contract. At 26, Riley is not likely to get another opportunity should this one pass unfulfilled.

Riley set up Rick Bragnalo's game-winning goal against St. Louis in his first Capital Centre appearance of the current trial, and team president Peter O'Malley observed. "A lot of people were talking about Riley when they left the building."

Riley scored his only NHL goal in the 2-2 tie with Detroit Jan. 4. He has aggressive, scoring a onesided fistic decision over Boston's Gary Doak, and at this moment his future could go either way.

McNab few to New Haven last night to watch the Capitals' Springfield farmhands. On the basis of earlier reports, he said that defenseman Bob Paradise was "playing very well with no discomfort," while left wing Blair Stewart was "not there yet." Paradise, with pulled stomach muscles, kept his legs in shape by running: Stewart out eight weeks with a broken right leg, is in need of conditioning.

The Islanders, three points behind first-place Philadelphia in the Patrick Division, are led by Denis Potvin, who last year won the Norris Trophy as the NHL's outstanding defenseman. Their No. 2 goalie is Billy Smith, brother of Washington defenseman Gord Smith.