Digital signal integrity (which means true to the original) does *NOT* rely on perfectly looking, clean 0 and 1 rectangles. It relies on signal thresholds and timing.
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Is Digital Audio Transmission Analog? [video]
- Thread starter amirm
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Incandescent turn indicator bulbs are perceptibly slow. You can see them come on and off more slowly than the on/off signal they are fed, Some LED's that respond more rapidly look too abrupt for what we are used to seeing. Some newer cars slow that signal so the LED's aren't so abrupt in action. None of which has anything to do with much of anything regarding Fourier and square waves.
That is a work of genius,
yet, cars made 50 years ago and this year are all legal and safe on the road, everyone can see and understand the indicator lights of all kinds.
go figure ....
You don't think that might be because the frequency of the square wave is so low (1 HZ?) that it is possible to fit very high multiples of that frequency down the still bandwidth limited wiring of even 50 year old cars? Say the 20 thousandth harmonic (just to pick one that is relevant in this forumyet, cars made 50 years ago and this year are all legal and safe on the road, everyone can see and understand the indicator lights of all kinds.
go figure ....
) should be easily transmissible.Hence the bandwidth limit is many many times higher than the fundamental, and as far as our eyes are able to detect it is not distorted (Beyond the distortion of the speed of the incandescent bulbs themselves - as mentioned by @Blumlein 88 ).
No its not an approximation. Its as exact as all proper math. Find a video on limits and calculus. Infinity is used in math all the time.
And if you filter a square wave you can extract any or all the sines, which means there already there they are NOT created by the filter. Filters don't create anything they FILTER.
For that matter, perfect analog square waves don’t exist either. Infinite bandwidth doesn’t exist.
A lot of the digital waveforms I deal with are almost sinusoidal. No one told them they need to be perfect square waves. And at >100MHz, they are seldom even close.
DonR
Major Contributor
Reactance is a sinusoidal function, all loads have some reactance (infinite bandwidth is not a thing), therefore, all signals are comprised of sinusoids.
you offer an exaggerated example to make a point.You don't think that might be because the frequency of the square wave is so low (1 HZ?) that it is possible to fit very high multiples of that frequency down the still bandwidth limited wiring of even 50 year old cars? Say the 20 thousandth harmonic (just to pick one that is relevant in this forum
Hence the bandwidth limit is many many times higher than the fundamental, and as far as our eyes are able to detect it is not distorted (Beyond the distortion of the speed of the incandescent bulbs themselves - as mentioned by @Blumlein 88 ).
Just as my friend was talking about some car manufacturers applying rise time manipulation to car indicators to make them even better!
please!
It doesn't matter how one skins this cat, for as long as it remains within spec.
For digital audio transmission through a conductor in a hifi environment , for as long as the DAC can read and lock onto data perfectly, all analogue distortions, artefacts etc. are irrelevant.
I still stick to my guns, that within a limited use environment, a square wave is just that! a car indicator system is but one example.
If you broaden our environment, then things change.
How about like this:
BTW, many people here on this very thread, have stuck to their guns, I suppose that qualifies them for being wrong.
This whole discussion gets even more pointless if you talk about digital transmission for TV etc.
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SAE Standard J590b specifies 60 to 120 blinks per minute. So 1 or 2 hz indeed.You don't think that might be because the frequency of the square wave is so low (1 HZ?) that it is possible to fit very high multiples of that frequency down the still bandwidth limited wiring of even 50 year old cars? Say the 20 thousandth harmonic (just to pick one that is relevant in this forum
Hence the bandwidth limit is many many times higher than the fundamental, and as far as our eyes are able to detect it is not distorted (Beyond the distortion of the speed of the incandescent bulbs themselves - as mentioned by @Blumlein 88 ).
DonR
Major Contributor
Sounds like a job for a new range of Nordost car wiring.
Wrong again. Thats the kind of logic I would expect. Have you looked at the videos posted? Did you learn any Fourier theory? Your uneducated guessing is useless.How about like this:
View attachment 247362
BTW, many people here on this very thread, have stuck to their guns, I suppose that qualifies them for being wrong.
Enough of this.
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Rats, there goes a decade of college and over 40 years of experience down the drain... Took the Internet to make me realize how wrong I was.
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DonR
Major Contributor
Always does. Did you know that the lizard people are hiding the truth about flat earth from you as well? It's all there on the internet, look it up.
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