We found this frequency meter circuit in a 1974 documentation. The circuit is powered by 12 V and has 8 digits. Changes can be made using a prescaler to reach higher frequencies.
This adjustable oscillator has the traditional configuration already presented in other articles. The...
This circuit appears in other versions on this site. obtained from other publications. This is...
This circuit decodes a 1800 Hz tone used in communications. The circuit is from an American...