super-plam

The applications and advantages of phase locked loop (PLL) systems have already been discussed in Elektor (Elektor, April 1975). In this article a practical design is discussed for a superhet receiver featuring a Phase Locked demodulator for AM signals, hence the name. The receiver is versatile in that it allows the user to choose between a wide or narrow i.f. pass band, and also between a conventional envelope detector or a novel synchronous detector using a PLL