Voltage controlled volume control. The input terminal connects through a 470 k ohm resistor to ground. The input terminal also goes to the positive end of a 3 microfarad capacitor. The negative end goes through a 22 k ohm resistor to pin 1 of the IC. It is labeled MC1496 or LM596. Pin 1 also goes through another 22 k ohm resistor to a point we will call point A. Pin 4 of the IC goes through yet another 22 k ohm res to point A. There is a 4.7 k ohm res from point A to ground. There is another 4.7 k ohm res from point A to minus 12 volts. Point A goes to the negative end of a 30 mike cap. The positive end is grounded. There is a 20 k ohm res connected between pins 2 and 3 of the IC. This is the only connection to these pins. Pin 5 goes through a 62 k ohm res to ground. Pin 14 goes to minus 12 volts. Pins 8 and 10 each go through a 4.7 k ohm res to ground. Pin 8 goes through a 620 k ohm res to a point labeled control input. Pin 10 goes through a 470 k ohm res to the wiper of a 5 k ohm trimmer pot. The top of the pot goes through a 12 k ohm res to plus 12 volts. The bottom of the pot goes through a 12 k ohm res to minus 12 volts. The top of the pot goes through a 680 ohm res to ground. The bottom of the pot goes through a 680 ohm res to ground. This pot is the zero volume adjust. Pins 6 and 12 each go through 30 k ohm resistors to plus 12 volts. Pin 12 goes through a 100 pf cap to ground. Pin 12 also goes to the positive end of a 3 mike cap. The negative end of the cap goes to the noninverting input of an op amp labeled TLO74. This is one of the 4 op amps in the IC package. The noninverting input also goes through a 30 k ohm res to ground. Pin 6 goes to the positive end of another 3 mike cap. The negative end goes to the inverting input of the op amp. The inverting input also goes through another 30 k ohm res to the output of the op amp. The inverting input goes through a 100 pf cap to the output. The output of the op amp goes through a 470 ohm res to a point labeled output. Although not shown, the power connections of the op amp go to plus and minus 12 volts. There is no actual ground terminal on an op amp. End verbal description.
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