This commercial receiver from the year 1958 uses two AA cells as Power supply. The circuit is intend to receive MW station and the transistors are germanium types not easy to find today.
This antenna for the frequencies 146 or 440 MHz was found in a magazine 73 for Amateur Radio of...
This circuit produces 1 kHz square signals using the CMOS IC 4070. The frequency is given by the...
Found in a 90s PE Hobbyst Handbook, this circuit mimics the sound of a space gun. The components...