SUFFOLK, Va. (AP) _ Friday marked the last day of work for 230 employees of General Electric Co.'s 20-year-old television factory here, which is closing because of competition from cheaper televisons made overseas.

Only one assembly line will continue to operate, but only through November, said Richard Knoph, the plant's manager of communications.

When that line stops, no TV sets with a GE brand will be produced in this country, said GE corporate spokesman Jack Batty at company headquarters in Fairfield, Conn.

Most of GE's TV sets already are imported, Batty said, ''sourced'' by Matsushita Electric Corp., of Japan.

A total of 790 jobs will be eliminated at the plant by early next year, Knoph said, with the largest number of hourly workers laid off Friday.

''There's a lot of dignity going out the door with these people,'' he said. ''The factors that are affecting their jobs are external. They're market- driven. They leave today knowing that their leaving is not their fault.''

He said the plant's quality of production for the last quarter was its highest ever.

The laid-off employees will receive severance pay averaging $12,000, insurance coverage for a year and job retraining, Knoph said.

They are first in line for any jobs that open at other GE plants within 250 miles, but Knoph said none of those plants is hiring new workers.

The Suffolk facility will remain a headquarters for GE's consumer electronics business and will employ between 300 and 400 people, he said.

The shutdown was announced a year ago, Batty said, to give workers time to find other jobs. ''It wasn't done quickly or overnight,'' he said.

RCA Corp., which GE acquired earlier this year, continues to produce TV sets in this country.