Universal multimeter UT139C with a high resolution will be appreciated at development and everywhere, where you need to find out a situation in a given device accurately
Imagine a situation, when you need to check or set a voltage of 3.3V or 5V usual at digital electronics (AD converters reference,…). Or to measure the end of recharging of Li-ion/ Li-Pol batteries at 4.20V when it really matters on every miliVolt. In these cases, with usual multimeters you´ll face one cardinal fact – regarding that the most of them has a max. display reading of 1999, you´ll measure in hardly the first quarter of a range, thus with a significantly lower resolution. For example instead of desired 4.001 V (3 decimal positions), you´ll only see 4.00V. Naturally, we don´t always need such a high resolution but many times an improvement of resolution in one magnitude can provide us a worth information about a real situation in a measured circuit. In these situations it often doesn´t matter on the absolute accuracy that much, but right on a resolution, especially when comparing voltages in two points, increase/ decrease…
From this point of view is the novelty in our stock UT139C an excellent device providing besides a high resolution (5999) also another features worth to notice, for example: TRUE RMS measurement in a range of 45Hz-1kHz (to 400 Hz with VFC filter activated), measuring of high-capacity capacitors up to 99.9 mF (99 999 uF), measuring of duty cycle in a range of 0.1% – 99.9% and other. Not quite common is also measuring of uA and mA even in AC range. Function Rel is useful even at measuring of small capacitors, where it´s able to eliminate “offset” caused by a capacitance of testing leads.
A thermometer (K type) with arrange of -40 to 1000°C can also be useful at development. From some point of view it´s advantageous supplying by two AA cells, not by a classic 9V battery (AA cells have a better capacity/ price ratio).
For more detail: With the UT139C you´ll find out why 5999 is better than 1999
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