Analog:
An analog phone starts off as a circuit connected to a battery, which sends electrons around the loop. Then we add the microphone towards the start of the loop. This blocks electrons from going past the microphone when no one is speaking. When the microphone hears a compression wave (sound), it lets some electrons through that copy that message. Then when the sound stops, we receive expanded electrons; the microphone stops letting the message through. This process continues as someone talks to convey the whole message through the wire as electrons. This can be viewed as compressed electrons, the ones that were let through for the message, then expanded sections of no electrons in between to represent the spaces when we speak. Some of these electrons are lost due to heat while moving through the wire. This is why we install amplifiers to correct the missing electrons due to heat. But heat isn’t our only issue. We also have noise electrons that can enter the wire. This noise wasn’t intended in the message but will still be picked up. These noise electrons are then amplified, as the amplifier cannot tell the difference between the two. This process continues until the message gets to the desired place. The further the place, the more amplifiers, and thus the more diluted the message gets by noise.
This was proof read by chatgpt.
Digital:
A digital phone starts in the same way as an analog phone. The first difference is how the microphone captures the sound. This time it will be represented as a graph that reads in the sound waves. When the graph is peaking, then those are compressed waves being picked up. When the graph is shallow, those are the expanded electrons we see. This graph is then labeled with time on the x-axis and y-axis; we are actually not labeling the lines across but the spaces between those lines. We record the number where the line is at across a standard interval along the time axis. Then, after the microphone, we introduce an analog-to-digital converter which does what I explained with the graph and gives the sound waves a series of numbers to represent where the wave was throughout the time of the message. Now, these numbers wouldn’t give us any noise on the other side of this message. So that means we need to use a digital-to-analog converter to turn those numbers back into analog sound waves. The number of bits determines the clarity of the sound, and the bits were the interval we were recording the sound at earlier. However, there is such a thing as too many bits; if there is too large of a number, then the system will lag, and you will receive the messages in small parts as the computer is trying to process all the bits. So these numbers are sent the whole way and then finally converted to the analog waves by the ADC. This also explains why better internet costs more because it can send more numbers in a short period of time. The numbers, however, can only be represented in binary, so they are transmitted as 1s and 0s. 0s mean send no electrons and 1s send 6 of these electrons through. This digital signal is still susceptible to noise electrons being added along with heat, making us lose electrons. To stop this, we install a digital amplifier that will correct these differences. Since the message is in 1s and 0s and the 1s are represented by 6 electrons, the system will see we have 115401 when it should really be 006600. The converter knows that it should only be sent 0 or 6 electrons. This allows it to change the numbers to be just 6s and 0s. The amplifier simply rounds the number to whichever it was closest to, such as 4 goes to 6 and 1 goes to 0. This fixes the noise dilution problem from the analog phone and gives a much clearer message when using digital.
This was proof read by chatgpt.