This circuit has its frequency controlled by a 1MHz crystal. The circuit must be powered by a voltage of 5V. The capacitors must be ceramic. The generated signal is rectangular.
This 1-transistor reflex receiver was found in a 1963 publication. The coil is for the mid wave...
Found in a European magazine from the 90s, this circuit emits beeps that are several seconds apart to...
This interface or shield circuit for instrumentation was obtained in a publication from the 90's....