Found in an old Radio Electronics, this circuit applies to frequency meters for frequencies up to 100 MHz. The input impedance is in the order of 1 M ohm.
This circuit is from American documentation from the 70s. This configuration appears in this...
This circuit uses a switch to select the direction of rotation of a DC motor. It was found in the...
Found in a 90s Electronics Engineering, this circuit makes use of components of the time. The...