Radio Weirdness

My friend was changing his guitar the other day when we discovered something interesting. When he touched the metal on the guitar we heard radio coming from the amp. We got the AM station 1430 coming out of the guitar amp! We figured that it was some how related to the Boss distortion pedal (the orange one), since we were using ourselves as the antenna without the guitar and the level knob was changing the radio frequency. Any one know why this happened? Zach