Addendum # 1, June 2015: Not so good for measurements behind USB batteries (Power Bank)
Recently I wanted to measure how much mAh external battery up to its max. may make possible discharge of an electrical load.
At the end of the measurement of the battery switches off to protect against deep discharge. Unfortunately, this instrument does not have its own power supply, so that it is also turned off and the measured data are gone. :-(
A measure of the net battery capacity is with this instrument not possible.
Addendum March 2015:
Meanwhile, there is also a device of similar function and similar price, but with a better display.
Keyword: PortaPow USB Power Monitor power meter (v2)
Old post ...
In addition to the information of Hippo I want to say ...
1) Perfect would this meter if the display would be illuminated because optimal ambient lighting conditions are rare, especially in the field. The current consumption of a tiny built-in LED is unlikely to significantly affect the power source and would probably loosely classify under "Tolerance".
2) The jacket (the same insulation) of the stick by means of a slide (probably a heat shrink tubing, but transparent) affects not just trust-inspiring. When the tears times, then the drive must be re-wrapped. Where there are transparent shrink tubing? Because Tesaband is unlikely to last.
