Charles Matthews, a lifelong Washington resident, became the first student at Hilltop Radio-Electronics Institute, a black-owned electronics school open to African-Americans in Washington, D. C. After graduating, he was hired in 1948 by the Army's cryptologic service at Arlington Hall. As an engineering technician, he worked in the Research and Development organization. Even though his white counterparts, with equal or less experience, received better pay, his $2,100 salary was better than most African-Americans were earning in other positions in the Agency.

Initially, Mr. Matthews tore down equipment, but later he became a project engineer on ABNER 1, the first in-house designed digital computer. He was one of a few African-Americans on the project. He also worked on SOLO, the Agency's first transistorized special-purpose computer. He went on to hold a succession of supervisory and middle-management positions and received the Meritorious Civilian Service Award in 1986. Mr. Matthews retired in 1988.