The bottom input terminal goes to ground. The top input terminal goes through a .1 mike cap to the grid of half of a 12AU7. The grid goes to ground through a 470 k ohm res. The cathode goes to ground through a 3.3 k ohm res. There is a terminal connection at the cathode labeled feedback. The plate goes through a 270 k ohm res to plus 250 v. The plate also goes through a .1 mike cap to the grid of section 1 of another 12AU7. The grid of section 1 is grounded through a 470 k ohm res. Both sections of this tube are used. Each cathode goes through its own 1.8 k ohm res to ground and in parallel with each res is a 50 mike cap. Each plate goes through its own 100 k ohm res to plus 300 v. The plate of section 1 goes through a .1 mike cap to the top output terminal. The plate of section 2 goes through another .1 mike cap to the bottom output terminal. The two output terminals are labeled to output tube grids. The top output terminal goes through a 430 k ohm res then a 33 k ohm res to ground. The junction of the two resistors goes to the grid of section 2. The lower output terminal goes through a 470 k ohm res to ground. End verbal description.
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