There’s only static when the signal is bad and some delay due to the travel time of signals, but analog broadcast never lags or stutters like TV and radio broadcasted over the internet.
Also, what makes it possible for thousands/millions of analog TV’s and FM radios to view and listen to broadcasts without causing issues when TV and radio broadcasted over the internet requires packet scheduling and lots of servers to serve the same number of viewers and listeners?
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Digital TV broadcast is like a delivery service: you communicate with a service, order the product and it gets delivered to you specifically, as well as any other customer. You will get your package but if a delivery man with one of the parts gets stuck in a traffic jam, expect lag.
FM radio and analog TV are like tap water. No individual deliveries, no feedback from your side, just take the pipework (analog TV cable network or broadcast at specific frequency) and fill ALL of it with your product. Whoever needs it, opens the tap from their side and gets a portion.
Second approach is less selective and requires special infrastructure, but that infrastructure allows the signal to spread in all directions with little extra effort. Basically, a radio tower is like a giant TV screen seen from far away. No matter how many people are looking at it, it won’t affect the broadcast.
Analog signals take essentially zero time to decode. When a signal gets to your eyes, it’s always analog, so the process of receiving, decoding, and processing a digital signal to what your eyes actually see adds delay. Even if the signal is bad, the badness is passed along in the form of static or lines, and the TV just moves on without trying to fix it.
Millions of receivers can tune into any signal, *but* if the signal is *two-way*, then they start competing for the transmitter’s attention. Analog signals can’t really be two-way, but digital signals can. One-way digital signals can also exist, they just usually aren’t used because two-way allows for error correction and such.
Think of an analogue broadcast like music from a loudspeaker, If the speaker is loud enough, you are close enough or have good enough hearing you can hear it no matter what, and anyone nearby can hear it instantly.
Digital broadcasts are broken up into tiny packages. You have to grab them, open them and put them all back together to understand the message, that’s where the lag comes from because a computer has to do that work.
When you watch a digital broadcast over the internet it doesn’t come through the air directly from a transmitter, it has to come through your internet connection and contend with everything else going back and forth through that connection.
This is more of a distinction between broadcast protocols vs the internet, rather than analog vs digital. Radio, analog TV, *and* digital over-the-air/cable/satellite TV are broadcasts. Think of it like the radio/TV station is shouting its signal into the air really loudly, and any device within earshot can choose to tune in and listen to it if they want. There’s no extra work for the station to do when a new listener/viewer tunes in. In fact the station doesn’t need to know at all who’s tuned in, or even how many people are.
The internet on the other hand is more like a big mail delivery service. When you watch a video on the internet, your device is sending a letter to the server saying “I’d like to watch XYZ, can you start sending me the data”, and the server starts sending it over to you by chopping it up into packets and mailing them all in sequence to your address. So the more people connected, the more “mail” has to be delivered. Note that this is how internet “live streaming” works as well. It’s all “mail” under the hood, just that everyone is asking for the same packages at the same time.
This is because analog TV and radio are broadcast. A huge transmitter outputs many kilowatts of radio energy. Almost all of that ends up striking trees, houses, soil and just generating a little heat, or travels out into space and is lost. But some tiny amounts of that energy are picked up by antennas across the reception area. The amount picked up is tiny – milliwatts, microwatts or even picowatts – but it is enough for the receiver to amplify and decode. The circuitry to decode is relatively simple, and works in real-time.
Digital TV is also sent out in a similar way – the digital stream is encoded onto a radio signal, that is broadcast by the transmitter, and picked up by receivers and decoded. Even cable TV and satellite TV works the same way.
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