ok so i'm restoring a kyosho beetle with the origional body and all. so the origional speed controller wasnt working. so i desided t install a grasshopper speed controller. its a direct fit. so as soon as i turn it on,(the system is a Sanwa Dash original to the car) so anyways, i put the bec in the battery slot on the receiver. then i turned on the radio and pluged in my 7.2 volt battyery. i turned around to pick up my radio, and smoke is just poring out of the receiver! this hapened in my bedroom lol and after it hapned, the whole house smelt like burned electronis. lol. note to self: dont do that again lol!