Many audio mixer circuits have been published but this this very simple audio mixer circuit uses only one transistor. The base emitter junction of the transistor is biased by the diodes D1 and D2.The signals to be mixed are directly coupled to the base of Transistor. Each input lines are current limited by using a 10k Potensiometer . With the used component values the collector current is around 1mA.
- The circuit can be assembled on a Vero board.
- The circuit can be powered from 9-25V DC.
- of each channel can be set using Variable resistor 10k
Transistors in the following series is enabled as a source of constant flow. By providing input audio signal on the emitter, the voltage on the emitter will fluctuate, which will cause the collector voltage also fluctuates. The amount of frequency fluctuation is comparable with the frequency of the incoming audio signal.