You are on the right lines mentioning pixels but as it stands there is a limit to size reduction but its an ongoing task as they know where it is lacking.
Even my new 4K PC with expensive video card and expensive monitor still cant achieve a good oscilloscopes resolution.
But I will see if cutting edge technology is achieving results.
Even my new 4K PC with expensive video card and expensive monitor still cant achieve a good oscilloscopes resolution.
But I will see if cutting edge technology is achieving results.
I think much of the limitation comes down the resolution of the ADC in digital oscilloscopes as well.
the problem with 100 mega sample scope is you need many samples to make up waveform. so that 100 mega samples will display a half decent waveform at 1mhz.
i find quite a few a2d's also tend to be a bit noisy.
I am trying to transcend ' samples '
As close to real time as possible
NO memory
Some circuitry to make virtual columns and rows on some type of flat display .
As close to real time as possible
NO memory
Some circuitry to make virtual columns and rows on some type of flat display .
The same digital engineering principles apply to digital audio test and harmonic test generators.
The professional ones are highly accurate/stable / can do all sorts of fancy types of signal shapes and so on and I can buy them second hand from a UK government agent at a fraction of the new price --why ?
Because their distortion values cannot go down to -100 db or more on a pure sine wave unlike many discrete analogue versions I have built out of the pages of EW entirely due to the fact they are digital.
But if anybody has a purely digital audio oscillator ( audio chips are not digital but linear amplifiers ) then please tell me the make / model that has a specification of a PURE sine wave at -100db or more .
If I am out of touch with the latest equipment please let me know but it must be purely digital NO cheating with linear amplifiers in the mix.
The professional ones are highly accurate/stable / can do all sorts of fancy types of signal shapes and so on and I can buy them second hand from a UK government agent at a fraction of the new price --why ?
Because their distortion values cannot go down to -100 db or more on a pure sine wave unlike many discrete analogue versions I have built out of the pages of EW entirely due to the fact they are digital.
But if anybody has a purely digital audio oscillator ( audio chips are not digital but linear amplifiers ) then please tell me the make / model that has a specification of a PURE sine wave at -100db or more .
If I am out of touch with the latest equipment please let me know but it must be purely digital NO cheating with linear amplifiers in the mix.
On a crt you may get 100-200 lines of resolution meaning you can divide the screen real estate that fine. Some special CRTs were capable of more. Scope CRT's less so since they were optimized for speed. A 547 had exceptionally sharp spot on the crt but was limited to less than 100 MHz. Tek revised the internal workings of the CRT to get higher deflection rates but the spot became fuzzier. its a tradeout.
The digital scope you are comparing to has a digitizer that may be 8 or 12 or even 16 bits. That translates into 256, 1024 or 65,536 values. However then you need to translate those numbers into something on a screen, usually an attempt to emulate a traditional scope. The better higher end scopes do a pretty good job with variable persistence and more updates per second but learning how to get those is not trivial. And learning how the translation from analog to bits to an x-y display can 'lie" is important.
I use both and a traditional (Tek 7K) or a digital (Siglent) are largely interchangeable for basic measurements. For one shot transients the digital scope is exceptional compared to even analog storage and for some specialized stuff it just lies.
The digital scope you are comparing to has a digitizer that may be 8 or 12 or even 16 bits. That translates into 256, 1024 or 65,536 values. However then you need to translate those numbers into something on a screen, usually an attempt to emulate a traditional scope. The better higher end scopes do a pretty good job with variable persistence and more updates per second but learning how to get those is not trivial. And learning how the translation from analog to bits to an x-y display can 'lie" is important.
I use both and a traditional (Tek 7K) or a digital (Siglent) are largely interchangeable for basic measurements. For one shot transients the digital scope is exceptional compared to even analog storage and for some specialized stuff it just lies.
I once owned a Tek 547 along with others including a tube storage version , the analogue one I use now only has a sensitivity of 5mV/DIV with a sharp trace but I remember some very old ones (tube based ) that went down to 1mV/DIV or even less .
They were all built like tanks and you needed good floorboards due to the weight but the pre BJT input versions could stand big overloads ,the 6080 tubes weren't that good though (heater/cathode shorts).
They were all built like tanks and you needed good floorboards due to the weight but the pre BJT input versions could stand big overloads ,the 6080 tubes weren't that good though (heater/cathode shorts).
No way to emulate rows and columns ?
Even @ say 100 kHz bandwidth ?
1 " pixel " lit @ a time ?
No memory, frame buffers, et. al.
To make the display you need to digitize the input map that to a display for both amplitude and time and then render it to a screen mapping the stored level vs time to specific pixels and then rasterizing it. in the far distant time people would use the magnetic deflection of a TV crt to acts as a low bandwidth scope. You cannot do that with an LCD.