This circuit was found in a 1963 magazine, but can still be easily assembled with some current components. The transistors may be the BC558 and the transformer is obtained from a disused transistor radio. The coil consists of 40 + 40 turns of yarn 28 on an approximately 12 cm long ferrite rod. The antenna is 30 to 50 cm and the range is a few meters in the range 550 to 1600 kHz.
