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.
The circuit presented is from the National Semiconductor's Linear Applications Handbook of 1994. We...
This is one of the many versions we have of a 12 V power supply with the 7812. We found it in the...
This fader or fader was found in a 90s Popular Electronics. The circuit uses transistors that are...