Unlike the non-coherent tuned radio receiver, the superheterodyne does not select the radio station within the RF amplifier. The key idea of the superheterodyne is to transfer useful information from the selected radio frequency into the intermediate frequency (IF). No matter what station the user selects, the superheterodyne produces an intermediate signal of the selected station at the same frequency. The programming is transferred into the intermediate frequency and most of the selecting (or filtering one station from others) and amplifying is done by the IF amplifier. The IF amplifier is easy to build because it amplifies a single frequency and has no tuning circuits. It is the IF amplifier that has many tuning stages, all of them built to amplify a single frequency.