Mickeyboyd, wrong, wrong wrong. Dual conversion is when the reciever uses two IF frequencies, typically 10.7 MHZ for the first conversion and then 455 KHZ for the second conversion. Basically, the reciever crystal (on a dual conversion receiver) is either 10.7 MHZ above or below the transmitted frequency. The IF (intermediate frequency) is then amplified and then mixed with another crystal to give a second IF of 455 MHZ. This is then amplified and decoded and sent to the servos. A single conversion reciever skips the 10.7 MHZ portion--converts to an IF or 455 KHZ immediately. Both systems work as well as far as sensitivity goes, dual conversion is usually better able to handle some forms of interferance, especially second order harmonic distortion.