By tykhon11/06/2018I made some measurements of this device. And wrote a detailed review of it at mysku.ru/blog/china-stores/60323.html
Main idea: the device does its job. Notwithstanding the fact that it has plastic gears and not so good handle, it can produce energy with all declared voltages. One man can easily charge a phone for a small call in couple of minutes.
So, according with my investigation, the efficiency of this device is about 0.22
The generator can be used as a motor.
Conclusion: it cost its price, especially
By yespinky08/12/2017only tried so far with USB but didn't need to crank fast (around 60 rpm). showed steady power to devices. with a load it will be tougher to crank but it's got gears and the longer handle makes that easy. great device! sheet of instructions was in Chinese only but no instructions really necessary. I'll Google translate for myself what the warnings say just in case!
bavuh
Wrote 2171 days ago.
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