In this figure 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 will be discussed in a moment. 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. To the right of the tubes are two transformers. Although they are identical they serve different functions in the circuit. The one closest to the tubes will be called the feedback transformer and the one farthest from the tubes will be called the output transformer. 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 connects to a pair of terminals labeled output. The bottom terminal goes back to the bottom of the secondary of the feedback transformer. Remember that these transformers are identical. The top end of the feedback transformer secondary goes to a tap near the bottom end of the output transformer secondary. The top and bottom ends, plate connections, of the feedback transformer primary are not connected. The screen grid taps on this ultra linear transformer connect to the cathodes of the output tubes as follows. The top tap connects to the bottom tube. The bottom tap connects to the top tube. The center tap of the primary goes to ground. End verbal description.
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