machine gun sound generator

24 machinegun- soundgenerator Computer games are even more fun when they are accompanied by sound effects. As most such games have a more or less destructive character, a machinegun-sound gene- rator will often come in very handy. The circuit consists of three nearly identical generators of which the output signals are added in a particu- lar ratio. This gives the impression that there are three machinegun posts. Each sound generator consists of three astable multivibrators (AMVs) which are connected in series by diodes. Each AMV can only oscillate if the output of the preced- ing AMV is logic 0. Two of the gener- ators have a preset potentiometer R13 7-44 NlrN2 143 6I 12 R9 R9 C4 Ri0 R11 cs R12 1M 02n ó FG2 820n 820n 1M 62n N7 N8 N9 N10 N11 N12 6 a D1 z to °a 12 15 R14 C10 39F 7 5 C9 R20 R21 C9 fNf 0 Rt6 P17 C7 R16 R19 3 9 11 1a 62- R20n N13 N14 D5 N15 N16 °6 N17 N18 6 a 7 5 2 10 3 9 12 15 R1s 20k 11 14 N1... N6= IC1=4049 N 7 ... N 12 = 1C 2 = 4049 N13... N18=1C3=4049 Dl ... ...