Orijinal gönderinin sahibi: E Carson ,
If you really want to test a charger, you should subject it to charging conditions, and monitor voltage over time. Cheap chargers are usually nothing more than a transformer rectifier with a few capacitors thrown in to smooth the output. This can lead to a relatively "dirty" output with microsecond power spikes or drops when the current exceeds what the capacitor buffer can handle. If I remember correctly USB +5VDC is rated to 500ma or one half of an ampere. Ohms law suggests a 5W 10ohm resistor. If you have an Oscilloscope handy probe the chargers output under load and set the scale to one volt per division or less, and click through the time ranges. The trace should stay steady! If not the devices may be rejecting the input.