Keywords: Superheterodyne receiver block diagram 2.svg superheterodyne radio receiver Invented by Edwin Armstrong in 1918 during World War 1 the superheterodyne is the design used in almost all modern radio receivers The incoming radio signal from the antenna left is first passed through an image rejection filter attenuate signals at the image frequency amplified in a radio frequency RF amplifier then mixed with an unmodulated sine wave from a local oscillator in a nonlinear transistor called a mixer This produces a beat frequency or heterodyne at the difference between these two frequencies a lower frequency called the intermediate frequency This is bandpass filtered in several stages of tuned IF amplification and applied to a demodulator which extracts the audio modulation sound from the radio carrier wave This is amplified by an audio amplifier and applied to the speaker <br/><br/> Superheterodyne receiver block diagram svg is identical to this image except it doesn't show the image rejection filter 2016-01-08 own Chetvorno other versions cc-zero Superheterodyne circuits Uploaded with UploadWizard |