This is audio mixer circuit. The circuit is for one channel input, if you need, for example 5 channel mixer, then you need to build 5 similar circuits.
TR1,2 = FCS9015 ; TR3 = C1213 ; IC1,2 = 741 or TL071
The kit of this circuit is available on the market, took the picture from electronic store in my town. This circuit is absolutely works.
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