The lower input terminal is grounded. The upper input terminal goes through a .01 mike cap to the grid of section 1 of a 12 A X 7. The cathode of section 1 goes through a 3.3 k ohm res, then through a 10 k ohm res, then through a 100 ohm res to ground. The junction of the 100 ohm and 10 k goes to a terminal labeled feedback. The junction of the 10 k and 3.3 k goes through a 470 k ohm res to the grid. The plate of section 1 goes through a 270 k ohm res to plus 250 v. The plate of section 1 of the 12 A X 7 also goes through a .1 mike cap to the grid of section 1 of a 12 A U 7. The cathode of section 2 of the 12 A X 7 goes through a 3.3 k ohm res then a 10 k ohm res to ground. The junction of the two resistors goes through a 470 k ohm res to the grid of section 2. The plate of section 2 goes through a 270 k ohm res to plus 250 v. The plate also goes through a .047 mike cap to the grid of section 2 of the 12 A U 7. The grid of section 1 of the 12 A U 7 goes through a 300 k ohm res to point A. The grid of section 2 of the 12 A U 7 goes through a 1 meg ohm res to point A. Point A is grounded through another 1 meg ohm res. Point A also goes through a .01 mike cap to the grid of section 2 of the 12 A X 7. The two cathodes of the 12 A U 7 are tied together and go to ground through a 1.5 k ohm res. Each plate of the 12 A U 7 goes through its own 24 k ohm one half watt res to plus 300 v. The plate of section 1 of the 12 A U 7 goes through a 510 k ohm res to the plate of section 1 of the 12 A X 7. The plate of section 2 of the 12 A U 7 goes through a 510 k ohm res to the plate of section 2 of the 12 A X 7. Each plate of the 12 A U 7 goes through its own .5 mike cap to each one of the two output terminals. Each output terminal goes through its own 100 k ohm res to ground. The two output terminals are labeled to output grids. End verbal description.
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