Comparison of the advantages and disadvantages of ordinary multimeters and digital multimeters:
Analog and digital multimeters have their own advantages and disadvantages.
The pointer multimeter is an average value meter, which has an intuitive and visual reading indication. (The general reading value is closely related to the pointer swing angle, so it is very intuitive).
Digital multimeters are momentary style meters. It takes a sample every 0.3 seconds to display the measurement results, and sometimes the results of each sampling are very similar, not exactly the same, which is not as convenient as the pointer type for reading the results. Analog multimeters generally do not have an internal amplifier, so the internal resistance is small.
The internal resistance of the digital multimeter can be very large due to the internal use of an operational amplifier circuit, often 1M ohms or more. (ie higher sensitivity can be obtained). This enables less impact on the circuit under test and higher measurement accuracy.
The pointer-type multimeter uses discrete components to form a shunt and voltage divider circuit due to its small internal resistance. So the frequency characteristics are not uniform (relative to digital), and the frequency characteristics of digital multimeters are relatively better. The internal structure of the pointer multimeter is simple, so the cost is lower, the function is less, the maintenance is simple, and the overcurrent and overvoltage capability is strong.
The digital multimeter uses a variety of oscillation, amplification, frequency division protection and other circuits, so it has many functions. For example, it can measure temperature, frequency (in a lower range), capacitance, inductance, be a signal generator and so on.
The digital multimeter has poor overload capacity due to the internal structure of multi-purpose integrated circuits, and it is generally difficult to repair after damage. DMMs have low output voltages (usually no more than 1 volt). It is inconvenient to test some components with special voltage characteristics (such as thyristor, light-emitting diode, etc.). The output voltage of the pointer multimeter is higher. The current is also large, which can easily test thyristors, light-emitting diodes, etc.
An analog multimeter should be used for beginners, and both meters should be used for non-beginners.
