INDEX-3 Reciprocity of antennas, 4-8 Reflection, atmospheric propagation, 2-11 Reflection of light, 1-30 Reflection, wave motion, 1-13 Reflections on a transmission line, 3-28 Refraction, acoustics, 1-23 Refraction, atmospheric propagation, 2-12 Refraction in the ionosphere, 2-20 angle of incidence, 2-22 density of layer, 2-21 frequency, 2-21 skip distance/skip zone, 2-24 Refraction of light, 1-30 Refraction, wave motion, 1-14 Resonance, acoustics, 1-24 Reverberation, acoustics, 1-24 Rhombic antennas, 4-42 S Safety precautions, if, 4-47 Selective fading, 2-27 Sound waves, 1-17 acoustics, 1-23 characteristics, 1-19 density and velocity of transmission, 1-22 requirements for sound, 1-18 terms, 1-19 Special antennas, 4-40 Speed of light, 1-30 Standing waves on a transmission line, 3-43 T Temperature inversion, 2-35 Terminating a transmission line, 3-38 Termination, 3-43 Terminology, 3-2 Transmission line theory, 3-10 Transmission losses, radio wave propagation, 2-27 freespace loss, 2-28 ground reflection loss, 2-28 Transmission mediums, types of, 3-2 Transverse waves, 1-5 Tropospheric propagation, 2-36 application of tropospheric scatter, 2-38 tropospheric scattering, 2-37 Turnstile antenna, 4-45 V V  antennas, 4-41 Variations in the ionosphere, 2-29 irregular variations, 2-30 regular variations, 2-29 Velocity of wave propagation, 3-24 Voltage change along a transmission line, 3-18 W Wave motion, principles of, 1-2 characteristics, 1-9 in water, 1-3 longitudinal waves, 1-5 medium, 1-6 terms, 1-7 transverse waves, 1-5 Wave propagation, 1-1 electromagnetic spectrum, 1-33 electromagnetic waves, 1-33 light waves, 1-25 principles of wave motion, 1-2 sound waves, 1-17 Wavelength to frequency conversions, radio waves, 2-8 Wavelength, wave motion, 1-8 Wavelengths and frequencies, 1-27 Weather versus propagation, 2-34 precipitation attenuation, 2-34 temperature inversion, 2-35 Working aloft, precautions, 4-49