Commercial television stations in the Washington area have asked the Federal Communications Commission to prohibit a new Arlington cable TV company from carrying signals of Baltimore's three network stations. The FCC is expected to rule on the matter Aug. 2.

Last summer, the regulatory agency granted Arlington Telecommunications Corp. (Artec) the right to carry the signals of Baltimore stations WMAR (channel 2, CBS), WBAL Channel 11, NBC) and WJZ (channel 13, ABC). Artec already had been granted the right to carry 12 other stations, including all Washington stations, two Richmond stations and an independent Baltimore station.

Subsequently, five local stations contended in a petition to the FCC that allowing Artec to carry the Baltimore stations would likely cause them great economic harm.

Stations seeking the ban on Baltimore broadcasts to Artec subscribers are WRC (channel 4), owned by the National Broadcasting Co.; WTTG (channel 7), an ABC affilate owned by former Washington Star publisher Joe Allbritton; WDCA (channel 20), an independent station being acquired by Taft Broadcasting Co., and WDVM (channel 9, formerly WTOP) a CBS affilaite recently purchased by Evening News Association of Detroit from the Washington Post Co.

The Washington stations charged that Artec's evidence of little potential economic harm to them is insufficient and of questionable validity.

Artec responded that the Baltimore stations already are widely available to Arlington viewers, primarily through master antennae on apartment buildings. Therefore, Artec says, making those stations available by cable should have little effect on the number of people watching the Washington stations. Artec further argued that few people in Arlington watch the Baltimore stations anyway.

But the Washington stations said few people watch the Baltimore stations because they get better reception of the local signals. A cable would equalize the quality of reception of signals from the two cities, the Washington stations said, resulting in a loss of viewers for them. Artec is planning the largest cable TV operation here to date, a 360-mile system aimed at up to 72,000 Arlington County homes.

FFC rules limit the number of "distant" stations that a cable TV company can offer Baltimore stations are considered distant because they are more than 35 miles from Arlington and they do not meet the test of being "significantly viewed" in Arlington.

The FCC granted Artec a waiver of its normal rules last July to allow Artec to carry the Baltimore stations as local rather than distant stations, thus allowing Artec to offer other distant stations. The FCC also then permitted Artec to classify WBFF (channel 45), an independent station in Baltimore, as a local station rather than as a distant one.

Artec said that being able to carry the Baltimore stations is essential if its proposed system is ever to be built. Artec plans to offer several experimental services with its systems, including five education channels.