We found this circuit in a 1982 documentation. It uses a CA3140 or equivalent operational amplifier and does not require a symmetrical source. The output is 1 Vpp wide.
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...