1-74
ANSWERS TO QUESTIONS Q1. THROUGH Q46.
A-1. Modulation is the impressing of intelligence on a transmission medium.
A-2. May be anything that transmits information, such as light, smoke, sound, wire lines, or
radio-frequency waves.
A-3. Mixing two frequencies across a nonlinear impedance.
A-4. The process of recovering intelligence from a modulated carrier.
A-5. The sine wave.
A-6. To represent quantities that have both magnitude and direction.
A-7. Sine ! = opposite side ÷ hypotenuse.
A-8. e = Emax sine !.
A-9. The value at any given point on the sine wave.
A-10. Phase or phase angle.
A-11. The rate at which the vector which is generating the sine wave is rotating.
A-12. The elapsed time from the beginning of cycle to its completion.
A-13. Wavelength = rate of travel period.
A-14. Process of combining two signal frequencies in a nonlinear device.
A-15. An impedance in which the resulting current is not proportional to the applied voltage.
A-16. The display of electromagnetic energy that is arranged according to wavelength or frequency.
A-17. At least two different frequencies applied to a nonlinear impedance.
A-18. Any method of modulating an electromagnetic carrier frequency by varying its amplitude in
accordance with the intelligence.
A-19. A method of generating oscillations, a method of turning the oscillations on and off (keying), and
an antenna to radiate the energy.
A-20. Plate keying and cathode keying.
A-21. Machine keying.
A-22. A high degree of clarity even under severe noise conditions, long-range operation, and narrow
bandwidth.
A-23. Antenna-to-ground capacitance can cause the oscillator frequency to vary.
A-24. To isolate the oscillator from the antenna and increase the amplitude of the rf oscillations to the
required output level.
A-25. To raise the low frequency of a stable oscillator to the vhf range.
