although for data or some function, it is not better than YZX meter, but for the price , it is already best …
for USB load, there are many choice , LD25/LD35
If someone need more cheaper meter, but colorful display, there is also choice AT34
Also, after reading your testing methodology, I still cannot understand how you perform the “USB coding test” to determine if it has AUTO CODING capability or not. Is there some device that can test that?
Also besides using an oscilloscope, any way we can test the noisiness of the power supply?
I have a problem testing 4 quick charge at a time and also more than 4 independent ports.
I have ordered one.
YZXStudio ZY1280 and ZL1100 are good for that, then scay for many protocols and list what is supported. Earlier I used a home made device that changed the voltage on the data pins, on the response I could see if it was auto coding.
A AC milivoltmeter, but bandwidth is important, something that just works to a few kHz is not good enough.
What kind of specs should have an oscilloscope for this job? I ask because the price for the cheapest is around 20 USD (DSO138) but I don`t know if is good enough.
You either have to use fully shielded setup (Cable from charger to scope is shielded) or you need to run you scope on batteries. I do the last and some of the noise is common mode noise from the charger.
The scope needs bandwidth enough, 10MHz would be fine for most cases and a input sensitivity that can can see the noise. I usual record two traces, the one I publish and another one with better sensitivity to read the actual noise level.
A USB type C cable round up would be nice where you test several cables off Amazon and gearbest. Data is very limited on these cables and they are very important and overlooked component.
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