Which is better, a pointer multimeter or a digital multimeter?
Features:
The digital type has a special block for measuring diode, while the pointer type does not. For the fluctuation of unstable parameters, the digital type is not as good as the pointer type, but the digital type has higher precision and clear display, unlike the pointer type which has to choose different scales according to different gears.
Working principle:
Pointer table is the use of electromagnetic induction plus simple electronic circuits to use, digital table is processed through digital circuits plus digital display word to apply! Pointer resistance measurement class is convenient, economical, durable, afraid of falling, reading is not convenient; digital table intuitive, high cost, general protection function!
1, pointer table reading accuracy is poor, but the pointer swing process is more intuitive, the swing speed amplitude can sometimes be more objective to reflect the size of the measured (such as measuring the TV data bus (SDL) in the transmission of data in the slight jitter); digital table readings are intuitive, but the process of digital change looks very messy, not very easy to watch.
2, pointer table generally have two batteries, a low-voltage 1.5V, a high-voltage 9V or 15V, its black pen is positive relative to the red pen. Digital meter is commonly used a 6V or 9V battery. In the resistance file, the pointer meter pen output current relative to the digital meter is much larger, with R × 1Ω file can make the speaker emit a loud "da" sound, with R × 10kΩ file can even light up the light-emitting diode (LED).
3, in the voltage file, the pointer meter internal resistance is relatively small compared to the digital table, the measurement accuracy is relatively poor. Some high-voltage micro-current occasions can not even be measured accurately, because of its internal resistance will affect the measured circuit (for example, in the measurement of the accelerated stage voltage of the TV tube when the measured value will be much lower than the actual value). The internal resistance of the digital meter voltage is very high, at least in megohm level, which has little effect on the circuit under test. But the very high output impedance makes it susceptible to the influence of induced voltage, in some strong electromagnetic interference occasions measured data may be false.
4, the head: it is a high sensitivity magnetoelectric DC ammeter, the main performance indicators of the multimeter basically depends on the performance of the head. The sensitivity of the head is the value of DC current flowing through the head when the pointer of the head is deflected to full scale, the smaller this value is, the higher the sensitivity of the head is. The greater the internal resistance when measuring voltage, the better its performance. There are four scales on the head of the meter, their functions are as follows: the first one (from top to bottom) is marked with R or Ω, indicating the value of the resistance, the conversion switch is in the ohms, i.e., read this scale. The second marked with ∽ and VA, indicating the AC and DC voltage and DC current values, when the transfer switch in AC and DC voltage or DC current block, range in addition to AC 10V other than the other position, that is, read this scale. The third is labelled with 10V, indicating the AC voltage value of 10V. When the changeover switch is in the AC or DC voltage block and the range is at AC 10V, this scale is read. The fourth bar is marked with dB, indicating the audio level.
5, the digital table must be charged to run (usually with 9V stacked battery). And pointer table in the measurement of voltage, current, no battery power supply. 6, digital table direct reading, pointer table reading is relatively less direct than the digital table. 7, in the dynamic measurement of voltage, current, digital table (digital table without oscilloscope function) is not as intuitive as the pointer table. 8, and in the seismic drop resistance, pointer table is far worse than the digital table. 9, the digital table function can be extended to measure the frequency, capacitance, Logic channel, transistor amplification, etc. And pointer table usually only resistance, voltage, current three files. I hope the above answer can help you to understand the difference between the digital table and pointer table.
