Abstract : The use of the radio-detection technique in a wide area cosmic-ray detector requires autonomous antenna stations, in terms of power feeding, triggering and data transmission. A prototype has been tested at the Pierre Auger Observatory. It uses the broadband (1-200 MHz) active dipoles already in operation in the CODALEMA experiment together with a solar power supply, an independent trigger electronics and a dedicated communication system. We present here the first evidence for radio detection of cosmic ray using autonomous trigger system in coincidence with the Auger surface detector.