Douglas Computer International has recorded a 93 percent increase in 1988 third quarter revenue over the same period last year.

For the period ending Sept. 30, the Salt Lake firm has earnings of $119,708, or 3 cents a share, on revenue of $1.7 million. That compares to the year before's net profit of $1,494 on revenues of $906,000.For the first nine months of 1988, Douglas Computer had revenue of $4.8 million - 55 percent improvement over last year's first nine months - and earnings of $284,907, or 8 cents a share.

The company attributed its improved performance to an stronger sales and marketing effort of its re-built and enhanced computer equipment.