John M. Holt retired in 2015 as the Director of Engineering and Operations of WAMU in Washington, D.C. Prior to that he was the Director of Engineering at Jefferson Public Radio in Southern Oregon, the Chief Engineer of Minnesota Public Radio’s Twin Cities operation and the Director of Engineering at New Hampshire Public Radio establishing the first station in 1981. Mr. Holt started his public radio career in 1974 at WMUK in Kalamazoo, Michigan. He is a collector of vintage microphones and a connoisseur of microphone and broadcast history.