Tunable FM booster

EE July/August 1986 36 by R Shankar 1 111 tuneable FM booster 01 BB106 C1 II Op 75 n BF961 BF981 This FM band (88-108 MHz) preampli- fier has been designed to come round the problems associated with wideband as well as narrowband aerial boosters. Most commercially available boosters are wideband types with relatively poor selectivity and adjacent station rejection, while the (more expensive) narrowband types are rather impracticable when it comes to receiving stations well removed from the (fixed) frequency of peak amplification. This proposed design is the best of both worlds, since it features good selectivity and strong signal hand- ling, as well as a relatively low noise figure and sufficient amplification over the entire FM band. Tuning the preamplifier is done in the living room, by means of a simple poten- tiometer mounted in an enclosure which is conveniently located next to the FM tuner as part of the hifi set. The unit can also be made to function as a 2 metres amateur b...