It depends. The high speed form
It's the natural tendency to make something out of nothing
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Is Digital Audio Transmission Analog? [video]
- Thread starter amirm
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It depends. The high speed form
It's the natural tendency to make something out of nothing
Wonder what a banker would say when he shows me the 0 on my account. And i would say relax at least it is a +0 and not a -0.
Suffolkhifinut
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He would offer you a loan based on your ability not to pay.Wonder what a banker would say when he shows me the 0 on my account. And i would say relax at least it is a +0 and not a -0.
Shoot, I had an example, must have deleted it when I pasted in the Wiki link, duh. Did I mention I'm an analog guy? Computers, blah...
10 decimal = 0000 1010 binary (using just one byte, 8 bits, to represent the number) = 1x10^1 + 0x10^0 = 10 + 0 = 1x2^3 + 0x2^2 + 1x2^1 + 0x2^0 = 8 + 2 = 10
-10 decimal = 1111 0110 two's-complement binary
In binary, the range of 8 bits is 0 to 255. Using two's complement, the range is -128d (1000 0000b) to 127d (0111 1111b).
HTH - Don
10 decimal = 0000 1010 binary (using just one byte, 8 bits, to represent the number) = 1x10^1 + 0x10^0 = 10 + 0 = 1x2^3 + 0x2^2 + 1x2^1 + 0x2^0 = 8 + 2 = 10
-10 decimal = 1111 0110 two's-complement binary
In binary, the range of 8 bits is 0 to 255. Using two's complement, the range is -128d (1000 0000b) to 127d (0111 1111b).
HTH - Don
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Limit theory... At the other end you have infinity aleph-null vs. aleph-one, the infinity of the continuum. In the primordial past I actually knew what all that meant.
In music, is Eb the same as D#? Depends upon the chord...
DonDish
Active Member
I think its the spacing in the wave not the direction on a vertical axis which defines 1 or 0. If you know what I mean. So a 1 or 0 could be either positive or negative. The signal is combined with carrier which is the clock. Somebody kick me in the nuts if im wrong about this.
Further a square wave isnt square, it just look that way. It can be defined by a (f)=x like any other wave. Just more complexity than a sine. Some people just have a hard time imagining a square wave. This wave will have trigger point, a corner, which will set off the next clock cycle.
With good enough signal quality and transport you could actually have triggers at each corner off the wave for a QDR transmission as in quad data rate. Clock can also be defined with a sine, some gear manufacturers do that.
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Raindog123
Major Contributor
Limit theory... At the other end you have infinity aleph-null vs. aleph-one, the infinity of the continuum. In the primordial past I actually knew what all that meant.
It’s actually very simple, even trivial!
Think of f(x)=1/x. For +0, it will become a very HUGE number (where is that banker!?)… while at -0, it’s rather ’very small’!
DonDish
Active Member
You guys couldnt even split a case of beer between youIt’s actually very simple, even trivial!
Surely -0 would result in a huge but negative number?It’s actually very simple, even trivial!
Raindog123
Major Contributor
I am not sure what this means. A "digital" signal is a sequence of bits (bitstream) that could in general be any pattern, e.g. 10101... or 100011011111000111... or whatever. Most high-speed serial interfaces recover the clock from the data stream, obviating the need for a separate clock line and attendant need to synchronize clock and data lines. Many standards (SAS, SATA, PCIe, etc.) encode the bitstream to prevent long runs of 1's or 0's that can cause the clock recovery circuit to lose lock (get out of synch with the signal) -- a PLL needs frequent transitions (edges) to phase-lock to the signal. There is not a carrier in the sense of an RF modulated signal that mixes LO (carrier) and IF/baseband signals to produce an RF output (or vice versa in the receiver).
How to make a square wave: https://www.audiosciencereview.com/.../composition-of-a-square-wave-important.1921/
AES or S/PDIF, as well as the aforementioned protocols, send a bitstream using a reference clock for Tx and the receiver recovers the clock from the signal. I2C and I2S are example of protocols that have an explicit, separate clock line.
FWIWFM - Don
Frankly, I do not support this explanation as a basic explanation. To me, square wave is created by a very fast switching transistor, from zero to fixed voltage and back. The transition time we can make shorter than 1ns. Fourier series or Fourier transform is just a secondary means how to describe a square wave in the frequency domain. I would certainly not use one million of sine waves to create a square wave.
You might not use 1 million sine waves, but the frequency content must be there to look "square'ish". But please provide a better explanation; I put that together based on Fourier decades ago to help explain the concept to college students. But many people have the same issue with it: that is, if you use a switching device or overdrive a pair of diodes to create a stepped (or toggled) square waveform, it is not obvious the relation to all the sine waves comprising the waveform. This is one of those things sometimes difficult to explain the relation between frequency and time domains. Working with data converters and pulse (radar etc.) systems I had it drilled into me early in my career. That said, when I created a square wave using SRDs (step recovery diodes) to generate fast (ps) edges, spectral analysis showed the frequency relations held per that old article.
No question that a square wave is made up of odd harmonics. I'll comment that it is a mathematical abstraction, albeit a useful one. IRL any system is band limited, so your square wave inevitably gets mooshed (that's the technical term).
It's not an abstraction if a square wave can be generated (IRL) by summing odd harmonics. The only abstraction is a perfect square wave, that doesn't exist IRL. Just because you chose to view the time domain version of the square wave as "primary" doesn't make the frequency domain version any less real or any less valid.
DonR
Major Contributor
Yes, put a LP filter on and see just how removing upper harmonics affects the square wave.
Yes, that's the point I was making. In addition, transformers are sometimes in the signal path, so you might get some high-pass action, too.
DonR
Major Contributor
For some reason now all I can think of is Rob Watts and his transient reconstruction claims.
Is that something he does with the homeless?
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