Balanced to unbalanced converter. On the left is a T R S jack. It is labeled balanced input and is also marked with the letter L. The S (sleeve) contact is grounded. The R (ring) contact goes through a 22 p f cap to ground. It also goes through a .1 mike cap to the noninverting input of op amp 1. The noninverting input goes through a 1 meg ohm res to ground. The output is tied to the inverting input. The T (tip) contact of the jack goes through a 22 p f cap to ground. It also goes through a .1 mike cap to the noninverting input of op amp 2. This input also goes through a 1 meg ohm res to ground. The output of O A 2 is connected to its inverting input. The output of O A 1 goes to one end and the wiper of a 5 k ohm trimming pot. The other end of the pot goes to a 7.5 k ohm res. The other end of the 7.5 k goes to the inverting input of O A 3. The inverting input goes through a 5.1 k ohm to the output. The output of O A 2 goes through a 10 k ohm res to the noninverting input of O A 3. This input also goes through a 5.1 k ohm res to ground. The output of O A 3 goes through a 470 ohm res to the center of an RCA phono jack. The shield is grounded. The jack is labeled unbalanced output and also with the letter L for left. The right hand channel is identical to the left and uses O A 4, 5, and 6. The input and output jacks are labeled with an R. O A 1, 2, 4, and 5 are labeled T L O 74. O A 3, and 6 are labeled T L O 72. Unbalanced to balanced converter. On the left is an RCA phono jack labeled unbalanced input and also the letter L. The shield of the jack is grounded and the center goes through a 22 p f cap to ground. The center also goes through a .1 mike cap to the noninverting input of O A 7. This input also goes through a 1 meg res to ground. The output is connected to the inverting input. The output of O A 7 connects through a 10 k ohm res to the inverting input of O A 8. The output of O A 8 connects through another 10 k ohm res to the inverting input. The noninverting input is grounded. The output of O A 7 goes through a 470 ohm res to the T contact of a TRS jack. The output of O A 8 goes through another 470 ohm res to the R contact of the TRS jack. The S contact is grounded. The jack is labeled balanced output and also with an L for Left. The right hand channel is identical except for using O A 9 and O A 10. O A 7 through 10 are labeled T L O 74. End verbal description.
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