https://www.antiqueradios.com/archives/ElementsOfRadioServicingCh1-4.pdf Try this link.....if it works.....Ken
Explaining radio or any EM wave is unfortunately an exercise in futility. We resort to easy to visualize sine wave examples and other analog diagrams which don't really answer basic questions that naturally arise when considering all aspects of the topic. For example, it is possible to fire one photon of light frequency at a target. If that single photon has a frequency, does it vibrate all by itself at that frequency? A frequency implies a wavelength. Does that mean if I instantly key down on my xmitter at 7mhz and release one photon, it is 40 meters long? This is no mind thought. A pair of famous physicists back in the 20s actually measured a photons length. And since E=mc**2, a massless photon in motion must have energy proportional to its frequency. And since space-time has an actual density as demonstrated by gravitational waves registering on the LIGO experiments, are a stream of our ham photons creating the wave we live by, by disturbing space-time as they propagate from one ham shack to another? Sounds like the old ether? It isn't but it is, sort of. Many brilliant physicists have said that our minds and world view makes us incapable of truly understanding quantum mechanics and cosmology. But many physicists and EEs have to do stuff, and do it by using what concepts and formula work to design antennas and improve magnetrons. That may be the best we can do at this time.
Explaining radio or any EM wave is unfortunately an exercise in futility. We resort to easy to visualize sine wave examples and other analog diagrams which don't really answer basic questions that naturally arise when considering all aspects of the topic. For example, it is possible to fire one photon of light frequency at a target. If that single photon has a frequency, does it vibrate all by itself at that frequency? A frequency implies a wavelength. Does that mean if I instantly key down on my xmitter at 7mhz and release one photon, it is 40 meters long? This is no mind thought. A pair of famous physicists back in the 20s actually measured a photons length. And since E=mc**2, a massless photon in motion must have energy proportional to its frequency. And since space-time has an actual density as demonstrated by gravitational waves registering on the LIGO experiments, are a stream of our ham photons creating the wave we live by, by disturbing space-time as they propagate from one ham shack to another? Sounds like the old ether? It isn't but it is, sort of. Many brilliant physicists have said that our minds and world view makes us incapable of truly understanding quantum mechanics and cosmology. But many physicists and EEs have to do stuff, and do it by using what concepts and formula work to design antennas and improve magnetrons. That may be the best we can do at this time.
The problem we face with radio waves (and quantum mechanics, for that matter) is that the mathematical and mental models we use to describe how they work do not have a good physical analogy. Sound waves in air, or ripples in water, can lead you to wrong conclusions. I think the best we can say is that our mathematical models for EM fields "work" - they give answers that are usable, measurements of the electrical properties with metering devices agree with the theory, and above all, radio works. The mathematical models may not be a true picture of 'reality' but they function well enough that we can use radio and electronic devices for practical communications, calculations, and so on. Our models are close enough that we can turn on a rig on the HF bands and hear signals from extreme distances, often transmitted with very little electrical power!
They are not in phase, they are in quadrature, meaning 90 degrees out of phase. Sine waves of equal magnitude that are in quadraure trace out a circle. The radius (total energy) remains constant.
You're absolutely right! It's fundamental to know this for all kind of hams here, regardless our years of experience. Greetings
