The quality of a lot of USB cables is rather poor when it comes to charging. Using a bad cable you can easily wait 20% longer for your phone to charge. The problem is that there is no obvious way to recognise a bad cable from a good one. They all look the same.
In this video I show how you can easily determine the internal resistance of a USB cable using only a USB power source, like a charger or power bank, a USB tester and LED light as load. I demonstrate the method using the Ruideng UM34C and the UNI-T UT658 USB tester.
I reviewed both of these earlier and you can find my reviews here:
UM34C review:
https://youtu.be/3yhHX96h-jgUNI-T UT658 review:
https://youtu.be/K7UxnF6LZtUThe power bank used in the video is a ASDA Blackweb 2600 mAh and you can find my review and tear-down of it here:
https://youtu.be/eHKbtBkfxKM