$ 0 0 Microlab M900 MC3500 _ Altec Lansing VS2521 _ MICROLAB X25D_X27D_H500D_H600D Circuit DiagramUsed ICs: 4558_4053_TDA2030 _ TDA7265M900 MC3500 Circuit Diagram Altec Lansing VS2521 _ MICROLAB X25D_X27D_H500D_H600D Circuit DiagramClick on the schematics to Magnify