Figure 8.6 A Typical All American Five Radio. One side of the line plug connects through the on/off switch which is part of the volume control to chassis ground. The chassis will be referred to as ground. The other side of the line plug connects to one side of the 35 volt heater of the rectifier tube and one side of the dial light. The other side of the dial light connects to the tap on the heater. This point connects to the plate of the rectifier tube. The plate is bypassed to ground by a .005 u f cap. The other side of the heater goes to one side of the 50 volt heater of the audio output tube. The other side of this heater goes to one side of the 12 volt heater of the I F amplifier tube. The other side of this heater goes to the heater of the converter tube. The other side of this heater goes to the heater of the detector and first audio amplifier tube. The other side of the detector and first audio tube heater goes to ground. The heaters form a series circuit. The cathode of the rectifier tube goes to the positive side of a 40 mike 150 v cap. This point is labeled high current B plus. This point goes through a 1 k ohm 1 watt res to the plus side of another 40 mike 150 v cap. This point is labeled low current B plus. The negative side of both caps is grounded. Both of these caps are usually in one unit called a dual cap.

The converter. On the left is a tuned loop antenna. It is an inductor which has been wound big so it can pick up the magnetic field of the radio waves. The top of the antenna goes to grid 3 of the converter tube. The top of the antenna also goes through one section of the tuning cap to ground. The bottom end of the antenna goes to a point labeled AGC. This point goes through a .1 mike cap to ground. The cathode of the converter tube goes to the tap on the oscillator coil. The bottom of the coil is grounded and the top goes through a 220 pf cap to grid 1 of the converter. Grid 1 also goes through a 22 k ohm res to ground. The coil is tuned by the other section of the tuning cap. Grids 2 and 4 of the converter tube are connected together inside the tube and are brought out to a single pin. This pin connects through a .01 mike cap to ground. This pin also goes through a 1 k ohm res to low current B plus. This same pin also connects to the low end of the primary of the first i f can. The high side connects to the plate. In the octal tube grid 5 is brought out to a separate pin and this pin is grounded. In 7 pin mini tubes grid 5 connects to the cathode inside the tube.

The I F amplifier. The top of the secondary of the I F transformer connects to the control grid of the i f amplifier tube. The bottom of the secondary connects to the AGC point. The cathode goes through a 68 ohm resistor to ground. The suppressor is grounded if it has its own pin or is connected to the cathode inside the tube. The screen grid connects to grids 2 and 4 of the converter tube. The screen grid of the i f tube also connects to the bottom end of the primary of the second i f transformer. The top of this winding goes to the plate of the i f tube.

The detector. The top of the secondary of the i f transformer goes to both diode plates of the duo diode triode which is the detector and first audio tube. The cathode of this tube is grounded. The bottom end of the i f transformer goes to a point we will call detector. The detector point goes through a 220 k ohm res and a 100 pf cap in parallel to ground. The detector point also goes through a 2.2 meg ohm res to the AGC point. The detector point also goes through a .01 mike cap to the top of the volume control 500 k ohm audio taper. The bottom end of the volume control is grounded. The wiper goes through a .01 mike cap to the grid of the triode section of the detector and first audio tube. This grid also goes through a 10 meg ohm resistor to ground.

The audio section. The plate of the triode goes through a 220 k ohm res to low current B+. The plate also goes through a .01 mike cap to the grid of the audio output tube. This grid also goes through a 470 k ohm res to ground. The cathode of this tube goes through a 120 ohm res to ground. There is a 20 mike cap in parallel with this res. The screen grid goes to low current B+. The suppressor grid is internally tied to the cathode. The plate connects to the bottom of the output transformer primary. The top of the primary connects to high current B+. There is a .001 mike cap in parallel with the primary. The secondary of the output transformer connects to the speaker voice coil. End verbal description.
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