Figure 7.2 Line Operated Transformer Coupled Amplifier. This circuit could have been the solid state version of the all American five but never quite got off the ground. The wide prong of the line plug connects to the bottom line of the circuit which we will call B minus. The other prong connects through a switch to the anode of a diode. The cathode goes to the positive side of a 30 u f 200 volt capacitor. The negative side connects to B minus. The positive side of the capacitor connects to one end of a 15 k ohm 2 watt resistor. The other end of this resistor goes to B minus through the parallel combination of a 1.3 k ohm resistor and a 22 u f capacitor. The junction of the two resistors and capacitor connects to the bottom of the secondary of an audio interstage transformer, single ended to single ended. The top of the secondary connects to the base of Q5, an N P N high voltage power transistor. The collector of Q5 goes to the top of an audio output transformer, 5 k ohm to voice coil. The bottom of the output transformer primary goes to the junction of the diode cathode and the 30 u f capacitor. The secondary goes to a speaker. The emitter of Q5 goes through the parallel combination of a 620 ohm resistor and a 33 u f capacitor. The resistor value is marked with a star and carries the note see text. The emitter also goes to a connection point labeled plus 12 volts to radio circuit. This plus 12 volt point connects to the bottom of the interstage transformer primary. The top goes to the collector of Q4 which is part of the radio circuit. Connections to the base and emitter of Q4 are not shown. End verbal description.
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