On the left is an air wound transformer. The number of loops in the symbol indicates that the primary has more turns than the secondary. The coil is labeled Hammond P dash C70 dash eh. The upper end of the primary connects to an antenna and the lower end connects to earth ground and circuit common. The lower end of the secondary also connects to circuit common. The upper end connects to the top of a variable capacitor which is labeled 30 to 365 p f. The lower end of the variable capacitor connects to circuit common. The upper end of the coil and variable capacitor connect to the parallel combination of a resistor and capacitor. The resistor is a 2.7 meg ohm and the capacitor is a 27 p f. The other end of the R C parallel combination goes to the gate of an F E T, M P F 1 0 2. There is a diode connected between the gate of the F E T and common. The cathode is connected to common. The diode is labeled 1N6263. The source of the fet goes to common. The drain of the fet goes through a 1 k ohm resistor to plus 12 volts. The drain also goes through a 0.1 u f capacitor to common. The drain also goes through a 1 u f capacitor to the center conductor of the output jack. The outer side of the jack goes to common. The end of the 1 u f cap the connects to the drain is marked with a plus sign. This completes the verbal description of the schematic diagram.

The oscilloscope screen shot shows an abnormal A M modulated wave near the top of the screen. The modulating signal is a sine wave. The modulation percentage is 90%. The positive peaks of the modulation envelope have been severely compressed and the negative peaks are much longer than they would be in a normal signal. Near the bottom of the screen is the recovered audio wave. The positive peak occurs at the maximum amplitude of the envelope of the AM wave. Although the recovered audio wave is distorted the distortion is less than for the above circuit. The scale setting for the A M wave is 200 mV per division and for the recovered audio is 500 mV per division. This completes the verbal description of the oscilloscope display.
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