My KCX-017 USB current and voltage tester

Sometimes you will face problem with USB charging such as charging speed slower than normal, unable to charge, or worse still, you encountered a "reverse charging" whereby current is drawn away from the battery of your device instead of charging it.

The problem could be due to faulty charger, faulty USB cable, or faulty USB port of the device to be charged.

In addition, certain 3rd party USB cables are having quality issue with unstable current flow, or only allow low current flow through it.

A USB tester such as the KCX-017 will be handy to diagnose such situations.

This small gadget only cost around RM25, and works well with wall charger, car charger, power bank, etc. by connecting its attached USB cable to the charger, or by connecting the charging cable to its micro-USB port. It will measure the input voltage and display on its LCD screen.

Its other end is a USB port which you can use a USB cable to connect to a charging recipient such as mobile phone, tablet, GPS navigator, etc. Beside the voltage, it will also measure and display the current drawn by the recipient, and also calculate the mAh value of the charging session.

In summary, this gadget is used to:

• Test no-load voltage of the power supply
• Test output power of USB output devices
• Test working voltage and current of the USB output devices
• Test voltage and line loss of charging cables
• Perform real-time monitoring of the charging status

Its specified working environment is as below:

• Voltage range: 3-7V
  
• Current range: 50mA-3,500mA
  
• Capacity range: 0-19,999mAh

When the input voltage is lower than 4.7V or higher than 5.3V, its LCD screen will flash with an arrowhead indicating under-voltage or over-voltage.

This device can record up to 10 sets of readings. There is a button near to its LCD screen.

• Double click the button, the display will start flashing. Single click the button to switch to different memory slot (from 0 to 9). Double click again to use the current memory slot displayed on screen.
• Long press the button will reset the next memory slot reading back to 0000.

This device is able to memorize the last reading when unplugged. The next time when it is turned on again, that reading will be displayed on its LCD screen.

It is a handy device to troubleshoot USB charging problem, as well as to test for the charging quality of USB cables.

My VST-706 3-in-1 car battery voltage monitor, digital thermometer and USB charger

I have just bought this VST-706 car gadget which plugs into the car cigarette lighter socket and function as 3-in-1:

• Battery voltmeter
• Digital thermometer
• USB 2.0 charger

This little car gadget cost less than RM30 and works with car using 12V battery or 24V battery.

The interpretation of its voltmeter reading is as follow:

Its thermometer measuring range is -9 ~ 80 degree Celsius.

The maximum output current of its USB charging port is 2.1A.

With it, you can always monitor the voltage of your car battery and be alerted of its faulty and timing for its end-of-life, before it went flat. The thermometer and USB charger are extra features that good to have too.

My SanDisk Ultra Dual USB Drive 3.0

The price of USB flash drive has eventually gone cheap. Nowadays, you can get a genuine 16GB SanDisk Ultra dual USB drive 3.0 with plug-and-play support to OTG-enabled Android devices at the price of less than RM20.

This SanDisk Ultra dual USB drive 3.0 has 2 connectors. At one end is a USB 3.0 connector that is able to transfer file to computer at a speed of up to 130 MBps (or about 1 Gbps).

Note that there is another product called "SanDisk Ultra dual USB drive" without the "3.0" behind, selling at slightly cheaper price, which the USB connector is a USB 2.0 connector and the data transfer speed is much lower than the 3.0 version.

At the other end is a micro-USB connector that can work on the fly with OTG-enabled Android devices.

Similar with the warranty period of most SanDisk Ultra range of products, this SanDisk Ultra dual USB drive 3.0 comes with a 5 years warranty.

Once plugged into the micro-USB port of the Android device, this USB flash drive is auto-detected by Android as one of the external storages and is immediately accessible by File Manager of Android system.

SanDisk also provides a free mobile app called SanDisk Memory Zone for user to access the USB flash drive and to transfer file between it and the device's internal storage or flash memory card installed in the device.

However, I found the function of this SanDisk Memory Zone app is very limited. It doesn't work with the folders in the USB flash drive so you can only copy file to its root directory, and the copying process is pretty slow.

The only Android app I found that can work with it without hassle is ES File Explorer Pro (or its free version ES File Explorer).

ES File Explorer Pro is able to detect and use this OTG drive upon plugged in, and all file operations of copying, moving, renaming, deleting, creating, opening with associated app, etc. can work well without problem.

ES File Explorer Pro works equally well to access my SanDisk Ultra Dual USB Drive 3.0 with my HTC One M8 smartphone running on Android 6.0 and my Samsung Galaxy Note 5.0 tablet running on Android 4.4.2.