DSB demodulator - electronic rotating field direction indicator

DSB demodulator elektor october 1982 — 10-17 Conventional amplitude modulation (AM) with carrier should by now be quite familiar. Short-wave, medium- wave and long-wave listening is very common because all the problems of this type of modulation appear to have been solved by the invention of the detector receiver. Nevertheless, for widely varying reasons, the field of telecommunications has provided the impetus to "invent" many other analogue and digital modulation methods; these are no doubt all justified but make quite different demands on the receiver. with respect to frequency stability of the demodulator. At this stage we would like to present another example of DSB which we encounter daily whilst hardly noticing it. We are referring to the stereo signal from the VHF receiver. Advanced radio enthusiasts will immediately point out that VHF radio operates with FM. This is true, but let us examine the stereo signal. It consists of the frequency band L+R, the pilot tone and two...