Found in a 90’s Popular Electronics, this circuit generates sinusoidal signals with frequency controlled by an input signal. C4, C3 and C1 together with R12 and R3 determine the frequency generated.
We found this circuit in the December 1998 issue of Electronics Now magazine. RF transistors such...
This circuit was found in an American documentation from the 80's. The sensor is a special...
This circuit automatically controls the degree of illumination. As the circuit is from 2001, it...