Telecom Systems Inc., an Arlington engineering services firm, has been bought back by founder Kieffer Knat of Reston from Telcom Inc. of Vienna, its former owner. As board chairman and chief executive, that will head TSI operations at several U.S. locations and projects in the Middle East, Europe, Latin America and Asia.

Sales of individual life insurance by Government Employees Life Insurance Co. in the first quarter were $54.5 million, up 13 percent from the 1979 period, President Thomas Hefner told stockholders last week. At the Waverly Press Inc. annual meeting, President William Passano Jr. said he is optimistic about the balance of 1980 despite lower first-quarter earnings, which he said reflected book purchases made late in 1979 to head off jan. 1 price increases.

Perpetual Federal Savings & Loan Association is moving most of its loan department operations from downtown D.C. to its branch in Silver Spring, mainly because of a lack of space in the city coupled with additional space in the Maryland suburban location after tenants moved out. Just a "housekeeping move," says Perpetual Chairman Thomas Owen.

Johnston, Lemon & Co. has published research reports recently on Flow General Inc., which won a key interferon contact last week; Scope Inc., which last week posted improved profits for the first quarter compared with the final three months of 1979; and Smithfield Food Inc., which is experiencing a strong rebound.