This 3-transistor buzzer or buzzer is a classic type found in the July 1998 issue of Electronics Now magazine. The power rating depends on the output transistor.
The quadrature oscillator is another type of phase shift oscillator, where each of the three...
This circuit was found in the November 1970 Radio Electronics magazine. Its function is to trigger...
This circuit is from a 1967 publication. The potentiometer above 4M7 is the critical component. The...