Five tube superhet. The antenna coil is labeled p dash c 70 dash a. The top, pin 3, of the antenna coil goes to the antenna. The bottom, pin 4, goes to earth and circuit ground. The bottom of the secondary, pin 2, goes through a .01 mike cap to ground. The cap is physically close to the antenna coil. Pin 2 also goes to the AGC line. The top of the antenna coil, pin 1, 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 a 220 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 B plus 2. The B plus 2 point goes through a .1 mike cap to ground. Pin 6 also goes to pin 3 of the R F interstage coil which is labeled P dash C70 dash RF. Pin 4 of this coil goes to pin 5, plate, of the 6 B A 6. There is a 47 k ohm resistor connected between pins 3 and 4 of the RF coil. The bottom of the secondary, pin 2, goes through a .01 mike cap to ground. The cap is physically close to the RF coil. Pin 2 also goes to the AGC line. The top of the RF coil, pin 1, goes to the signal grid, pin 7 of the converter 6 B E 6. The second 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 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, pin 2, on the oscillator coil. The coil is labeled P dash C70 dash O S C. The bottom, pin 3, of this coil is grounded. The top, pin 1, 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 variable cap called a padder connects from pin 1 of the coil to the top of the third section of the tuning cap. The other side of the tuning cap is grounded. A trimmer cap is connected in parallel with the variable capacitor. Grids 2 and 4 are brought to pin 6. This pin goes through a 1 k ohm resistor to B plus 2. 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 220 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 B plus 2. 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, 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 the yellow lead. This lead goes through a 100 pf cap to ground. This point 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 .001 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 B plus 2. Pin 7 of the 6 A V 6 goes through a .01 mike 200 v cap to the grid, pin 5, of the output tube, 6V6. A 470 k ohm resistor goes from pin 5 to ground. The cathode, pin 8 goes through a 220 ohm resistor to ground. The screen grid, pin 4, goes to B plus 2. A 47 mike 250 volt cap goes from B plus 2 to ground. A 1 k ohm 1 watt resistor goes from b plus 2 to B plus 1. B plus 1 also goes to the bottom of the output transformer primary, brown. The top of the transformer primary, blue, goes to the plate, pin 3, of the 6V6. A .001 mike cap goes from the plate to ground. The secondary leads, black and green, go to a 4 ohm speaker. Consult the transformer data for the leads to use for a different impedance speaker. The transformer is a Hammond 125 B S E. The heater of the 6V6, pins 2 and 7, go to the source of 6.3 volts. The wide prong of the line plug goes to the bottom of the power transformer primary. The narrow prong goes through a switch, then a fuse to the top of the primary. The transformer is labeled Hammond 269 A X. The center tap of the high voltage secondary is grounded. A .005 3 k V capacitor is connected from one end of the secondary to the other. Each end of the secondary connects to the anode of a 1N4007 diode. The two cathodes are connected together and also connect to the positive of a 47 mike 250 volt cap. The negative end is grounded. The point where the positive of the cap and diode cathodes come together is B plus 1. The 6.3 volt winding has two 150 ohm resistors connected in series across it. The junction of the two resistors is grounded. In a similar manner there are two .1 mike caps in series across the 6.3 volt winding. The junction of the two caps is grounded. End of verbal description.
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