I have seen a few planes "shot down" when someone without the frequency pin, turned on their radio. It is extremely sad when that occurs. I know of one member who quit the hobby in disgust when that occurred to him many years ago. He had about 500 hours building his prized plane and it was totaled on the first flight. On at least one occasion I have saved someones plane when I was standing near a flier with a plane in the air and he stated he had lost control of his plane. Because I knew the flier was experienced I concluded there was radio interference and I immediately yelled "radio interference, everyone turn off your radio". The guilty party turned off their radio and later thanked me for saving him from a bad outcome. On a few occasions I have screwed up and turned on my transmitter without having the required frequency pin. In a perfect world that has never happened to anyone else, RIGHT? That worries the heck out of me. On more than one occasion I selected the wrong frequency pin and tried to start the engine and wondered why nothing seemed to work. On other occasions I made a mistake and selected my wrong radio when I had more than one radio at the field. I am very careful when I fly and have been in R/C since 1972. It is by pure luck that I have never "shot" someone down. When I first saw what the 2.4Mhz radios could provide, I embraced it as a solution to the MAJOR problem I had with this wonderful hobby. I waited about one year for the bugs to show up and then converted my four planes to Futaba 2.4Mhz. My new radio is flawless and my major worry is no more. I have wondered why this is the first comment in this direction on this subject. Am I the only one that has made mistakes?