Designed for the audio track, this circuit was found in a Popular Electronics from the 90's. Other operational can be used and R7 can be 470 k. The frequency is 1 kHz.
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...