Reminder.....
Here's a picture of what your sock puppet says is too complicated/fiddly/generally impossible to do:
All the guy did was insert the cheapest, cheap-ass $3(plus shipping) Aliexpress amplifier into his signal path and the pink trace turned into the yellow trace.
There was no fiddling or messing around, just connect it up and it works. In this case it was inserted in the path of an AWG.
I don't know what more "proof" anybody could ask for.
Dear Fungus,
Now I see you don't understand what we are talking about. I apologize for not being clear enough.
Yes we can see some scope screen and some waveforms.
But that is exactly the point: you see
something on a screen.
And if all you need is to see if, for instance, you have clock on some pin it is fine like that.
But in that case even the original signal representation by noisy MSO5000 would be enough for GO/NoGO check.
But scope is not just used for scope art. We need to measure things. We need to see if signal is distorted.
We need to verify amplitude.
For that amplifier needs to be calibrated, it needs to have standardized input and output impedance. We need to have it
characterized for bandwidth, distortion, phase distortions..
When that "amplifier" is part of scope itself all that stuff is already done by scope manufacturer and included in scope specifications and calibrated.
Also since when you have a scope that has minimum 5mV/div, from that to 500uV there are 3 amplification steps missing (2mv, 1mv, and 500uV div). Are you going to have 3 different amplifiers? For what bandwidth? What input imepedance? Those 5 USD amplifiers are RF amps. They are 50Ω (they should be but nobody know if they are and what it's real impedance is, you need a VNA to measure it). They don't go to DC. You might find an amplifier that is high impedance (1MΩ//some pF) but with what BW? Is that one DC too?.
So, if you have a lab with several thousands worth of other equipment you might characterize and use your own preamps for specific purpose. And that is actually done all the time. People make custom preamps for specific purpose too.
But none of that is "replacement of fix" for scope limited range. It is an application specific thing that takes a lot effort and knowledge to be done right. None of it is "just throw in a preamp". And you might need dozens of different preamps and all the stuff that goes with it.
Fact is, and that is what I said before but it was not registered, there are oscilloscope preamplifiers. Basically those are scope front ends (the high sensitivity low noise ones, some even differential) with all the needed parameters already sorted out. Those can be (and are) used to purpose you are advocating. Problem with those is they cost so much, it is cheaper to buy SDS2354X HD (12 bit low noise one) than one of these fancy preamps.