I'm not sure if this interests anyone or if I am knocking on the right door, but...

I figured why not ask this question here amongst a sea of tech savvy folks such as yourselves =)

I'm a high school physics teacher, among other things, and have been oft accused of explaining things in an over-complicated manner =(

So... if anyone out there could enlighten me by answering the following question in a way that your stereotypical "smart" high school senior could follow, I'd much appreciate it. Also, a bit of clarification for me might be in order if my understanding of it is incorrect as this is my first year teaching physics. =/ I've taught other things for MANY years, but physics is a first. And, again, this doesn't have to be complicated. Probably the simpler the better, but I do want to include at least what I have mentioned below. Mention of transistors and other intricacies of the radio/television are not necessary unless they help the understanding.

How to simply explain analog vs digital transmission as in radio or television signals.

As I understand it and a wholly over-simplified analog explanation:
Transmitting

1. Sound waves are converted into electromagnetic waves that are coupled with a standard carrier wave.
2. These "message waves" (original sound waves) can alter the carrier waves amplitude (AM radio) or the carrier waves frequency (FM radio).
3. This coupled wave is amplified prior to transmission as it travels up the transmitter's "tower" to increase range of signal.
   Receiving
4. When you turn on your radio and tune it to a specific radio station, electricity moves through your antenna causing it to 'vibrate'.
5. When the antenna is subjected to a resonant frequency/amplitude, the antenna transmits that specific wave frequency/amplitude into your radio.
6. The coupled message is then 'separated' into the sidebands (the carried message). The radio 'selects' only vibrations with a specific range of frequencies (FM) or amplitudes (AM) within the bandwidth (sidebands x 2?). This helps cancel out any interference from other waves.
7. The vibration is converted into small voltages that are outputted as the original sound message.
   Digital Transmission/Reception:
8. Pretty much the same process, but the information is not transmitted/received via one stream on one carrier wave. It is sent as many, many packets of information coded into a stream of "on's" and "off's" (1's and 0's, aka binary code). The radio/tv assembles the message and converts it back into sound/video.

Analog v Digitial - Digital ensures better reception as interference is limited due to numerous packets of info. Assembling digitial transmission causes increased lag.

AM v FM - AM has longer range due to increased amplitude. FM has much wider variety because there is much more you can do with frequency than amplitude. This is why AM typically sticks with talk radio and FM plays many more sounds (like music). AM range increases at night when the ions in the ionosphere thin and acts as a "rebounding mirror". AM also can travel along the curved space of the Earth as FM really does not.

I've already run across the boat in the ocean analogy (rocking the boat = AM, waving your hand to create additional wave "patterns" = FM, and numbering hundred of ducks and letting a shore-man reassemble the ducks in the original pattern = analog). This helps, but the process of modulation and reception is what I really get stuck on.

Thanks if anyone is interested. 8)

not a physics person myself, but do like physics concepts

analog: waves (cosine functions)

digital: 2 specified values/levels of electricity/voltage/amp/current/whatever the correct term (lol), which are either flowing or not flowing, and that flow vs no-flow of the 2 specified values/levels of electricty/voltage/amp/current/whatever the correct term through logic gates on computer chips/microprocessor,s represented by '0' and '1' bits ("digital"), which are combined to produce more eleborate functionality computer parts/chips: transistors, flip-flops, half/full-adders, decoders, encoders, multiplexors, registers, memory unit types, counters, etc)

this is the text book we used for the computer architecture (circuitry) part of my 'assembly+computer-archecture' class (it's old, but it's still how computers work):

Computer System Architecture, 3rd edition, by M. Morris Mano (California State University, Los Angeles, California)
Prentice Hall, Englewood Cliffs, New Jersey 07632

AM vs FM vs XM:

AM has longer wavelength, so it can wrap around larger things (like hills/mountains: earth's curvature), and thus you can hear it in more places, but because it's a longer wavelength, it's not a very clear/"crisp" signal/sound

FM has a shorter wavelength, so it can only wrap around smaller things, meaning that it can't wrap around larger things, so location (hills/mountains: earth's curvature) can prevent you from hearing it (as it can't get to you), however because the wavelengths are shorter, the signal is more clear/"crisp"

and an even smaller wavelength, such as visible light radiation/spectrum, can bend only around even smaller things, such as maybe a tree or a pencil

and then there's quantum mechanics and bending too: ht.tps://www.youtube.com/watch?v=DfPeprQ7oGc

XM: ht.tp://electronics.howstuffworks.com/satellite-radio.htm

Xanmag
Sometimes a picture saves a 1000 words and for something like this, a picture (or video) is best.

This URL gives a very simple explanation of what the difference is between AM & FM radio. http://www.pbs.org/wgbh/aso/tryit/radio/
The 3rd link in the section More about radio... gives a very simplistic description especially FM vs AM: What's the Difference?
Also there are some good videos on YouTube. See these for some basics...
https://www.youtube.com/watch?v=QEubAxBfqKU
and https://www.youtube.com/watch?v=w3M4cqAMWQs

This link gives a comparison of all 3 forms of radio transmission. http://www.explainthatstuff.com/radio.html

These will give you a good understanding and save me from a lot of typing (and possibly a bit of mis-information) - Its been nearly 50 years since I learnt this stuff including designing and building my own AM & FM Transmitters & Receivers (TXs and RXs)

Pretty much the same process, but the information is not transmitted/received via one stream on one carrier wave. It is sent as many, many packets of information coded into a stream of "on's" and "off's" (1's and 0's, aka binary code). The radio/tv assembles the message and converts it back into sound/video.

I would guess it is sent as high or low frequency, rather than on or off.

Analog v Digitial - Digital ensures better reception as interference is limited due to numerous packets of info. Assembling digitial transmission causes increased lag.

Digital loses fidelity when the analogue sound is converted to a digital value (this is why some people still prefer vinyl records). Digital is robust because there is a significant difference between high and low and this is easy to discern at the receiver. It can also incorporate check digits, though whether radio/TV actually does that I am not sure. However, when interference is high, digital is lost entirely, as it is no longer possible to reliably discern between high and low.

I would guess digital requires more bandwidth, given one bit encodes only a high/low, while analogue encodes an actual frequency. In practice digital channels seem to be packed into a much smaller frequency range, but I wonder if that is another effect that could also be applied to analogue?