A friend of mine bought two of those units for his personal use. Upon arrival, he used one until it burned out. He brought the units over to a lab we have access to and showed me the units. Once he explained what he needed them for, I advised him to buy a real car inverter from Walmart. My friend passed them on to me, where i burnt the second one within minutes of plugin it in. I never used the usb port and later tests showed that it output 6 volts.

That is the original board. (NOT SHOWN: TO-92 Transitor, TIP41C Transitor, and a capacitor). I decided not to repair after seeing how made.

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