This circuit was found in a 1977 timer cookbook. The circuit can generate signals with up to 99% active cycle. The FET can be BF245 or MPF102 and the basic frequency given by R1, R2 and C1.
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...