This dual-band receiver was found in documentation from the 1970s. The original transistors are germanium, but modifications can be made to use modern silicon transistors such as the BC558 or even BC548, by inverting the power supply polarity. The coils are formed by 20 + 80 turns for medium waves and 5 + 25 turns for short waves, with 28-wire on a ferrite rod. The antenna must be long, and the output transformer is the type found in old transistor radios.
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