Due to a recent infusion of venture capital, Entre Computer Centers, the McLean-based franchising company that has opened 30 retail centers in the past six months, has announced plans to enter the national market this month and the international market next year.

In September, Entre attracted the backing of Smith Barney Harris Upham & Co. and Idanta Partners of La Jolla, Calif.

Entre is owned by co-founder and president Steven B. Heller, co-founder and vice president of marketing James J. Edgette, Idanta Partners and Smith Barney.

By entering the national and international markets, Entre officers expect to exceed the growth of the past six months during the first half of 1983.

"We anticipate having 50 to 60 centers in the U.S. alone by the middle of next summer," said Edgette.

Entre has 17 centers presently open and is constructing 13 more on the East Coast and in Texas.

Entre was established in 1981 by Heller and Edgette. The first store in McLean is still company-owned.

Heller had owned Acuity Systems Inc., which manufactured automated equipment for eye doctors, from 1971 until the late 1970s. Edgette was Acuity's national sales manager.

Before signing Entre's first franchisee earlier this year, Heller and Edgette had spent two years on planning and research. They developed a "cradle to grave" relationship model for themselves and their franchisees.

Entre franchisees are provided with site selection assistance, personnel training and technical, advertsing and promotional support. The retail centers purchase the entire Entre product line, geared to the professional small business and including the IBM Personal Computer and Atari and Televideo computers, from the company warehouse in Merrifield, Va.