Analysis of Advantages and Disadvantages Between Analog and Digital Multimeters
Comparison between pointer multimeter and digital multimeter: Both pointer and digital multimeters have their own advantages and disadvantages.
A pointer multimeter is an average value instrument with intuitive and visual reading indication. (Generally, the reading value is closely related to the pointer swing angle, so it is very intuitive).
A digital multimeter is an instantaneous style instrument. It uses sampling every 0.3 seconds to display measurement results, and sometimes the results of each sampling are only very similar and not exactly the same, which is not as convenient for reading results as pointer based methods.
A pointer multimeter generally does not have an amplifier inside, so the internal resistance is relatively small. For example, the MF-10 type has a DC voltage sensitivity of 100 kiloohms per volt. The DC voltage sensitivity of MF-500 model is 20 kiloohms per volt.
Due to the internal use of operational amplifier circuits, the internal resistance of digital multimeters can be made very large, often at 1M ohms or greater. (i.e. higher sensitivity can be obtained). This makes the impact on the tested circuit smaller and the measurement accuracy higher.
Pointer multimeters have low internal resistance and often use discrete components to form shunt and voltage divider circuits. So the frequency characteristics are uneven (compared to digital), while the frequency characteristics of a pointer multimeter are relatively better.
The pointer type multimeter has a simple internal structure, so it has lower cost, fewer functions, simple maintenance, and strong overcurrent and overvoltage capabilities. The digital multimeter adopts various oscillation, amplification, frequency division protection circuits inside, so it has more functions. For example, it can measure temperature, frequency (in a lower range), capacitance, inductance, and be used as a signal generator, etc.
Digital multimeters have poor overload capacity due to the use of multiple integrated circuits in their internal structure (although some now have automatic shifting, automatic protection, etc., but are more complex to use), and are generally not easy to repair after damage. The output voltage of a digital multimeter is relatively low (usually not exceeding 1 volt). It is inconvenient to test some components with special voltage characteristics, such as thyristors and light-emitting diodes.
The output voltage of the pointer multimeter is relatively high (including 10.5 volts, 12 volts, etc.). The current is also large (such as MF-500 * 1 Euro range with a maximum of about 100mA), which makes it easy to test thyristors, light-emitting diodes, etc.
