He did tours in Vietnam and Germany and served as an intelligence officer. While in Germany, he discovered Nazi cryptographic materials that were later placed at the National Cryptographic Museum at Fort Meade.
He left military service as a major, then joined the National Security Agency, where he worked to capture and prosecute spies. Family members said he worked on the federal prosecution in 1987 against U.S. naval officers John A. Walker and Jerry Whitworth, who passed classified documents to the Soviet Union.
Mr. Carter later received a Meritorious Civilian Service Award from the NSA.
After his retirement from the NSA in 2002, he joined government contractors Sparta Inc. and Prophasys Corp.
He also served on housing and development committees in Columbia. He was a replacement dispatcher for the Howard County Police Department, working holidays.
A memorial service will be held at 11 a.m. Friday at the Witzke Funeral Home, 5555 Twin Knolls Road in Columbia.
Survivors include his wife of 20 years, Barbara Matelock Carter, a retired Baltimore County teacher; a son, Mike Carter of Annapolis; a daughter, Laura Beth LeBlanc of St. Michaels; a brother, Evans Carter of Framingham, Mass.; a stepbrother, Norman Duxbury of Daytona Beach, Fla.; and three grandchildren. Marriages to Jeanne Gerber Carter and Peggy McCardle ended in divorce.