The voltage regulator value of the voltage regulator tube we usually use is generally greater than 1.5V, and the resistance file below R×1k of the pointer meter is powered by the 1.5V battery in the meter. In this way, the resistance file below R×1k is used. Just like measuring diodes, measuring zener tubes have complete unidirectional conductivity. However, the R×10k gear of the pointer meter is powered by a 9V or 15V battery. When using R×10k to measure a voltage regulator tube with a voltage regulation value less than 9V or 15V, the reverse resistance value will not be ∞, but a certain value. resistance, but this resistance is still much higher than the forward resistance of the Zener tube. In this way, we can preliminarily estimate the quality of the Zener tube. However, a good voltage regulator also needs to have an accurate voltage regulation value. How to estimate this voltage regulation value under amateur conditions? It is not difficult, just find a pointer watch. The method is: first place a watch in the R×10k gear, and the black and red test pens are connected to the cathode and anode of the voltage regulator tube respectively. At this time, the actual working state of the voltage regulator tube is simulated, and then another watch is placed on the On the voltage range V×10V or V×50V (according to the voltage regulation value), connect the red and black test leads to the black and red test leads of the watch just now, the voltage value measured at this time is basically this The voltage regulator value of the Zener tube. Saying "basically" is because the bias current of the first watch to the voltage regulator tube is slightly smaller than the bias current in normal use, so the measured voltage regulation value will be slightly larger, but the difference is basically the same . This method can only estimate the voltage regulator tube whose voltage regulation value is less than the voltage of the pointer meter's high voltage battery. If the voltage regulation value of the Zener tube is too high, it can only be measured by means of an external power supply (in this way, when we choose a pointer meter, it is more suitable to use a high-voltage battery with a voltage of 15V than 9V)
