eh R 15 power amplifier section. One side of the input is grounded. The other side goes through a 10 microfarad capacitor then a 10 k ohm resistor to the base of an NPN transistor. We will return to this point two more times. The emitter of this transistor is grounded. The collector goes through a 33 k ohm resistor to plus 27 volts. The collector also goes to ground through a 270 pf capacitor. The collector also goes to the base of the second transistor, another NPN. The emitter goes through a 330 ohm than a 1.8 k ohm resistor to ground. There is a 250 microfarad capacitor in parallel with the 1.8 k ohm. The junction of the 330 ohm and 1.8 k ohm goes to one end of a 270 k ohm resistor. The other end of this resistor goes to the base of the first transistor. The base of the first transistor goes through a 33 k ohm resistor to ground. The collector of the second transistor goes through a 3.3 k ohm resistor to plus 27 volts. The collector of the second transistor goes through a 250 microfarad capacitor then a 1 k ohm resistor to the base of the third transistor, another NPN. The base also goes through a 2.2 k ohm resistor to ground. The base also goes through a 33 k ohm resistor to a point will call the amplifier mid point. The emitter goes through a 270 ohm resistor to ground. The collector of the third transistor goes through a 330 pf capacitor to ground. The collector also goes through 3 diodes all in series, then through a 4.7 k ohm then a 1 k ohm resistor to plus 85 volts. There is a 50 microfarad cap connected from the amplifier mid point to the junction of the 1 k and 4.7 k ohm resistors. The collector of the third transistor goes to the base of the lower driver, a PNP. The junction of the 4.7 k ohm resistor and the anode of the upper diode goes to the upper driver an NPN. The collector of the lower driver goes through a 100 ohm resistor to ground. The collector also goes to the base of the lower output an NPN. The emitter of the lower driver goes through a 4.7 ohm resistor to the collector of the lower output. The collector of the upper driver goes to plus 85 volts. The emitter of the upper driver goes through a 100 ohm resistor to the amplifier mid point. The emitter of the upper driver goes to the base of the upper output also an NPN. The collector of the upper output goes to plus 85 volts. The emitter goes through a 0.67 ohm 5 watt resistor to the amplifier mid point. The amplifier mid point goes through another 0.67 ohm 5 watt resistor to the collector of the lower output. The emitter of the lower output goes to ground. The amplifier mid point goes to one end of a 2.2 microfarad capacitor. The other end of this capacitor goes through the parallel combination of a 330 k ohm resistor and a 2.7 pf capacitor to the base of the first transistor. The amplifier mid point goes to one end of a 4000 microfarad capacitor. The other end goes through am 8.8 microhenry coil to the hot speaker output. The amplifier mid point goes through a 0.001 microfarad capacitor to the hot speaker output. The hot speaker output goes through a 0.1 microfarad capacitor then an 11 ohm 5 watt resistor to ground. The cold speaker output goes to ground. End verbal description.
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