Comparison of advantages and disadvantages between a regular multimeter and a digital multimeter:
A pointer multimeter is an average type instrument that has intuitive and visual reading indications. (Generally, reading numerical values is closely related to the angle of pointer swing, so it is very intuitive).
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A digital multimeter is an instantaneous style instrument. It uses a sample taken every 0.3 seconds to display the measurement results. Sometimes, each sampling result is only very similar and not exactly the same, which is not as convenient for reading the results as a pointer type. A pointer type multimeter generally does not have an amplifier inside, so the internal resistance is small.
Due to the use of an operational amplifier circuit internally, the internal resistance of a digital multimeter can be large, often at 1M ohms or higher. (i.e. higher sensitivity can be achieved). This allows for less impact on the tested circuit and higher measurement accuracy.
The pointer type multimeter, due to its small internal resistance and the use of discrete components to form a shunt and voltage divider circuit. So the frequency characteristics are uneven (compared to digital ones), while the frequency characteristics of digital multimeters are relatively better.
The internal structure of the pointer type multimeter is simple, so it has lower cost, fewer functions, simple maintenance, and strong overcurrent and overvoltage capabilities.
The digital multimeter uses various oscillation, amplification, and frequency division protection circuits internally, so it has many functions. For example, it can measure temperature, frequency (within a lower range), capacitance, inductance, and be used as a signal generator.
Due to the use of integrated circuits in the internal structure, digital multimeters have poor overload capacity and are generally difficult 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, light-emitting diodes, etc. The output voltage of the pointer type multimeter is relatively high. The current is also high, making it convenient to test thyristors, light-emitting diodes, etc.
For beginners, a pointer type multimeter should be used, and for non beginners, two types of instruments should be used.
