GAITHERSBURG, MD. (WDVM) — Officially, the Army Security Agency was never in Vietnam.” But former Army Sergeant Larry Matthews says, “ASA was there and elsewhere in Southeast Asia monitoring the movement of North Vietnamese troops and Viet Cong guerillas.”

“Somebody had to go in there and do that and the Army Security Agency did it,” said Matthews as he talked about his involvement in the 3rd Radio Research Unit, “as though anyone would fall for that,” laughed Matthews.

ASA teams were the eyes and ears of U.S. military commanders during the Vietnam War. General Creighton Abrams is quoted as saying the Army Security Agency saved more American lives than any other unit, because it could tell where the NVA was, at what strength and what they were going to do. But the ASA paid a heavy price for that information.

“Unfortunately, we were not always listened to so that turned up some pretty bad results,” said Matthews as he reminded me that the first soldier killed during the Vietnam war was an ASA operator, Spc4 James Davis seen here operating a direction finder 20 miles northeast of Saigon in August 1961.

To monitor enemy Morse Code or radio traffic, ASA teams had to set up radio monitors and direction finders in open areas and that made them tempting targets.

Matthews remembers the night a DF unit mounted on a jeep and their Special Forces security team got a very strong signal. When the operators took off their earphones, they could hear enemy soldiers talking on the other side of some trees. The DF team managed to escape by putting the jeep into neutral and pushing it to where it was safe to start it and head back to base.

Close calls like that caused U.S. military commanders to rethink how they collected information about enemy activities. A reward for ASA personnel also played a part in their decision. “For that reason, General Abrams stopped sending out units like mine and shifted spying operations to planes,” said Matthews.

Those small low-flying aircraft packed with listening devices flew back and forth over the Ho Chi Minh Trail, the major supply route from North Vietnam to South Vietnam.

Some larger aircraft were lost while dropping electronic sensors along the trail to monitor NVA truck traffic.

Those sensors made Morse Code collection of enemy information obsolete during the Vietnam War. But the need for soldiers who could copy code resurfaced when the U.S. got involved in Afghanistan.

“The Taliban figured out that the U.S. Army was no longer copying Morse Code, so they started using it,” said Matthews, “And that forced the Army to drag out a bunch of old technology and start teaching Morse Code again.

When Larry Matthews left the Army in the mid-60s, he became an award-winning broadcaster at radio stations in Washington, D.C. a published author and podcaster.

Of all the awards that hang on the walls of his “man cave,” he is most proud of a framed photo of the men in his family who served for five generations in the military, his grandfather, father and son