Figure 8.5 Complete Push-Pull Amplifier. On the left is an input jack. The center contact of the jack goes to the top of R1, 500 k ohm pot. The bottom is grounded and the wiper goes to one end of C1, 0.01 u f capacitor. The other end of C1 goes to the grid of V1 eh. The grid goes through R2, a 10 meg ohm resistor to ground. The cathode of V1 eh goes through the parallel combination of R2, 1.8 k ohm, and C2, 10 u f, to the top end of R3, a 100 ohm resistor. The bottom end of R3 is grounded. The plate of V1 eh goes through R5, a 100 k ohm, to B plus 3. The plate of V1 eh also goes through C3, 0.01 u f to the grid of V1B. The cathode of V1B goes through R8, 10 k ohm then R7, 100 k ohm to ground. The junction of R7 and R8 goes through R6, 470 k ohm to the grid of V1B. The plate of V1B goes through R9, 100 k ohms to B plus 3. The plate of V1B goes through C4, 0.1 u f to the grid of V2. The junction of R7 and R8 goes through C5, 0.1 u f to the grid of V3. The grid of V2 goes through R11, 100 k ohms to a point labeled bias. The grid of V3 goes through R10, 100 k ohm to the bias point. The cathodes of V2 and V3 are connected together and to ground. The screen grids of V2 and V3 are connected together and to B plus 2. The suppressor grids of both V2 and V3 are connected to the cathode inside the tube. The plate of V2 connects to the top of the primary of the output transformer. The plate of V3 connects to the bottom of the output transformer primary. The center tap of the primary connects to B plus. One side of the secondary is grounded. The other side goes to one end of R14, 910 ohm. The other end of R14 goes to the junction of R3 and R4. The ends of the output transformer secondary go to the speaker terminals. B plus goes to ground through a 40 u f capacitor. B plus also goes through R12, 1 k ohm, to B plus 2. B plus 2 goes through C7, 40 U f to ground. B plus 2 goes through R13, 10 k ohm, to B plus 3. B plus 3 goes through C8, 22 u f to ground. End verbal description.
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