The Tomo Epilot E4 is available from Gearbest (black is a few cents cheaper than white); maybe there’s a generic coupon code somewhere to bring down the price…
While searching for the Tomo powerbanks, I came across other models too:
Tomo D2 (2x 26650) powerbank/charger: https://www.gearbest.com/chargers/pp_1524290.html
(specs list the input current @ 1A ; it will take a long time to fully charge 2x 5000+ mAh 26650 with this powerbank…)
but YZX meter did not have ,
For UM34C, it support USB 3.0 and Quick charge recognition mode:QC2.0、QC3.0、APPLE 2.4A/2.1A/ 1A/0.5A、Android DCP、SAMSUNG, support support OPPO phone VOOC, OnePlus DASH
Though UM34C and UM25C have Type-c port , but there is not trigger, only support type-c charge, not recognition
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.