Magnetic phono pre amp. Both channels are identical, only one will be described. The input phono connector goes through an 11 k ohm resistor to the noninverting input of the first op amp. The noninverting input goes to ground through the parallel combination of an 820 peko farad capacitor and a 36 k ohm resistor. The output goes to one end of a parallel combination of a 0.0033 microfarad capacitor and a 22 k ohm resistor. The other end of this parallel combination goes to the inverting input. The inverting input also goes to ground through a 2.4 k ohm resistor. The output of the first op amp goes to one end of a 10 microfarad non-polar electrolytic capacitor. The other end of this cap goes to one end of a 10 k ohm resistor. The other end goes to the inverting input of the second op amp. The inverting input goes through a 100 k ohm resistor then a 1 meg ohm resistor to the output. There is a 0.0033 microfarad capacitor in parallel with the 1 meg resistor. The noninverting input is grounded. The output goes through a 470 ohm resistor to the output jack. End verbal description.
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