With this circuit you can mix four separate audio inputs. Each input will accept high or low impedance microphones, phonograph, tape or aux signals.
I have had many requests to design or provide circuits for graduation projects. Yes, I had to build a graduation project too before receiving my degree. Even though I have always refused to design circuits for this situation, I thought it might be helpful for you to see what I built for my project many years ago when I graduated in 1978. I will also provide a more detailed description of the circuit than I normally do. Hopefully, this may help some of you with your projects.
I like to see lights move to music. This project will indicate the volume level of the audio going to your speakers by lighting up LEDS. The LEDS can be any color so mix them up and really make it look good.
This circuit will allow you to connect any tape recorder that has a mic and remote input to a phone line and automatically record both sides of a conversation when ever the phone is in use.