As most of you know, although I'm a very active participant in AAC's fora (because I love this place), I'm just a half-baked noobie when it comes to analog electronics. So I'm going to ask a few questions that may seem laughable to those versed in the elemental stuff of electronics and electromagnetism, but that are pretty deep stuff to me. I'd rather ask a dumb question and look stupid (and get the answers I want) than stay quiet and stay stupid.
In the next paragraphs, I'm going to make several statements explaining what I think I understand, and will also make several direct questions. I'll be very grateful for any corrections and clarifications related to what I'm about to say. Remember, my statements will actually be questions with the purpose of evaluating how much I really know about the subject.
Let's start with the way AM behaves, since I think it will be the easiest for me to understand at first.
Some of the biggest mysteries for me regarding radio AM ares these:
How many stupid things, wrong assumptions, and incomplete ideas have I said so far?
There are many other questions that I'd like to ask on this subject, but lets start with this few ones first.
In the next paragraphs, I'm going to make several statements explaining what I think I understand, and will also make several direct questions. I'll be very grateful for any corrections and clarifications related to what I'm about to say. Remember, my statements will actually be questions with the purpose of evaluating how much I really know about the subject.
Let's start with the way AM behaves, since I think it will be the easiest for me to understand at first.
- The modulation of a signal is related to the continuous change of one of its parameters, so as to encode information within it, that will later be extracted and demodulated (decoded) by a receiver.
- In the case of AM, the frequency remains constant, and the amplitude is changed to encode that information. So a constant tone of x-Hertz in AM would look like this:
Some of the biggest mysteries for me regarding radio AM ares these:
- Radio waves are particular zone within the electromagnetic spectrum that lies below a frequency of about 100 MHz
- Since radio waves are nothing more than photons of a certain frequency, and since the energy of a photon is directly related to its frequency, how is it possible to modulate its amplitude? In other words, what property of light is amplitude? It's certainly not color, from what I understand. Does AM work by changing the amount of photons being emitted by the antenna, and therefore the intensity of the signal?
- A radio emitter works by exciting the electrons in the atoms that form an antenna. Those electrons are raised to a higher orbit by energy being pumped into the antenna, and they later release photons when they return to their lower (and original) orbit. Those photons form what we call radio waves.
- A receiving antenna captures those photons, in such a way that they excite the electrons of the atoms of metal that form said antenna, and that change in their potential is later amplified and decoded by the receiver.
How many stupid things, wrong assumptions, and incomplete ideas have I said so far?
There are many other questions that I'd like to ask on this subject, but lets start with this few ones first.