Four tube superhet. The top, white, of the antenna coil goes to the antenna. The bottom, black, goes to earth and circuit ground. The bottom of the secondary, yellow, goes through a .01 mike cap to ground. The cap is physically close to the antenna coil. The yellow lead goes to the AGC line. The top of the antenna coil, green, goes to the grid, pin 1 of the R F amplifier 6 B A 6. One section of the three section tuning cap goes from pin 1 to ground. There is also a trimmer cap in parallel with the tuning cap. The heater, pins 3 and 4 go to the 6.3 volt source. The cathode, pin 7, goes through an 820 ohm res to ground. The suppressor grid, pin 2, goes to ground. The screen grid, pin 6 goes through a .1 mike cap to ground. Pin 6 also goes through a 1 k ohm res to plus 125 v. The 125 v point goes through a .1 mike cap to ground. Pin 6 also goes to the bottom end of the R F plate coil, 250 micro henrys. The top of this coil goes to pin 5, plate, of the 6 B A 6. Pin 5 goes through a trimmer cap to ground. Pin 5 also goes through one section of the tuning cap to ground. Pin 5 also goes through a 27 pf cap to pin 7 of the 6 B E 6. Pin 7 goes through a 47 k ohm res to the A G C line. The 47 k ohm res goes through a .01 mike cap to ground. This cap is physically close to the resistor. The heater, pins 3 and 4, go to a source of 6.3 volts. Grid 5 is tied to the cathode inside the tube and comes out to pin 2. Pin 2, connects to the tap, yellow, on the oscillator coil. the tap is closer to the bottom than it is to the top. The bottom, black, of this coil is grounded. The top, green, goes through a 220 pf cap to grid 1, pin 1, of the 6 B E 6. This grid also goes through a 27 k ohm resistor to ground. A trimmer cap is connected in parallel with the oscillator coil. Another variable cap called a padder connects from the top of the coil to the top of the third section of the tuning cap. The other side of the tuning cap is grounded. Grids 2 and 4 are brought to pin 6. This pin goes through a 1 k ohm resistor to plus 125 volts. Pin 6 also goes through a .1 mike 200 v cap to ground. Pin 6 also connects to pin 4, red, of the i f transformer. pin 2, blue, of the i f goes to pin 5, plate, of the 6 B E 6. The red and blue leads are the primary of the i f transformer. The top of the secondary, pin 1, green, goes to pin 1, grid, of the other 6 B A 6. The bottom of the secondary, pin 3, Yellow, goes through a .01 mike cap to ground. This cap is physically close to the i f can. The yellow lead from the i f can connects to the AGC line. The cathode of the 6 B A 6, pin 7, goes through a 390 ohm resistor to ground. The heater, pins 3 and 4, connect to the source of 6.3 volts. The suppressor grid, pin 2, is grounded. Pin 6, screen grid, connects through a .1 mike cap to ground. Pin 6 also connects through a 1 k ohm resistor to plus 125 v. Pin 6 also connects to the red lead, pin 4 of the second i f can. Pin 2, blue, of the i f connects to pin 5, plate of the 6 B A 6. The top of the secondary, pin 1, green, goes to pins 5 and 6 of the 6 A V 6. These are the diode plates. The cathode, pin 2, is grounded. The bottom end of the secondary is pin 3 on i f cans with pins. On those with wire leads this lead may be yellow or black. This lead or pin goes through a 100 pf cap to ground. This pin also goes through a 47 k ohm resistor to the top of another 100 pf cap and the bottom of this second cap is grounded. The junction of the resistor and cap goes through a 2.2 meg ohm resistor to the top of a .1 mike cap. This point goes to the AGC line. The bottom of the .1 cap is grounded. The junction of the 2.2 meg and 47 k resistors and 100 pf cap goes through a 220 k ohm resistor to ground. The junction of the three resistors and cap goes through a .01 mike cap to the top of the volume control. The bottom of the volume control is grounded and the wiper goes through a .005 mike cap to the grid, pin 1, of the triode section of the 6 A V 6. Pin 1 also goes through a 10 meg ohm resistor to ground. The heater of the 6 A V 6 goes to 6.3 volts. The plate of the triode, pin 7, goes through a 270 k ohm resistor to pin 6 of the second 6 B A 6. Pin 7 of the 6 A V 6 goes through a .01 mike 200 v cap to the output. A 4.7 meg ohm resistor goes from the output to ground. End of verbal description.
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