Mixing Console - Maker Factory ELECTRONICS EXPERIMENTS BOX Manual

2.64 Mixing console

Circuit 137: Input level mixing console
Setup information
Install the transistor, the ceramic capacitor and the three resistors as shown in Fig. 2.137. The three jumper
wires come next. Check the placement on the board again and only then connect the battery. If you are
familiar with the relevant safety guidelines as per VDE and know how to observe them when working with
devices that are to be connected to the mains, you can now connect the audio amplifier.
Experiment
If everything is wired correctly, you can safely go ahead and connect an mp3-player. You will hear your
music full volume coming from the audio system. The special feature in our circuit here, you can intercon-
nect two to five levels to one output. If each one gets a potentiometer at the input, we would have the input
part of an NF mixer. You will learn more in our next experiment about the suitable end stage for such a
mixing console.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.137.
Components required:
1 x J111 FET transistor,
1 x 2.2 kΩ resistor,
1 x 4.7 kΩ resistor,
1 x 1 MΩ resistor,
1 x 100 nF ceramic capaci-
tor, 1 x breadboard, 1 x 9V
battery with clip connector
Fig. 2.137: Input level Mixing
console
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