In figure E the input terminals are designated as driver plates. The upper input goes through a capacitor to the grid of the top output tube. This grid goes to a point labeled bias supply through a 100 k ohm res. The lower input similarly goes through a cap to the grid of the bottom tube and there is another 100 k res to the bias supply. The cathodes are tied together and go to ground. The screen grids are tied together and connect to a point labeled screen supply. The suppressor of each tube is tied to its cathode inside the tube. The plate of the upper tube goes through a resistor back to the plate of the upper driver. Similarly the plate of the lower tube goes through a res to the lower driver plate. The plate of each tube goes to one end of the output transformer primary. The center tap goes to a point labeled plate supply. The secondary of the output transformer is not connected to anything in this drawing. In figure F the driver tubes are shown as triodes. The grid and cathode connections are assumed. The top driver plate goes to the top end of the driver transformer primary. The bottom driver plate goes to the bottom end of the driver transformer primary. The center tap goes to driver B+. The upper end of the driver transformer secondary goes to the grid of the top output tube. The lower end of the driver transformer secondary goes to the grid of the bottom output tube. The center tap of the transformer secondary goes to a point labeled bias supply. The cathodes are tied together and go to ground. The screen grids are tied together and connect to a point labeled screen supply. The suppressor of each tube is tied to its cathode inside the tube. The plate of each tube goes to one end of the output transformer primary. The center tap goes to a point labeled plate supply. The secondary of the output transformer is not connected to anything in this drawing. End verbal description.
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