– August, 1902 ("barretter" detector) , "Receiver for Electromagnetic Waves" – May, 1903 (improved "barretter") Other Detectors of electrical oscillations Tech Definitions – Radio Concepts United States Early Radio History Secor, H. Winfield (January, 1917). Radio Detector Development. The Electrical Experimenter, pages 652+, accessed 2007-12-20. History of radio Radio electronics Detectors Canadian inventions