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What is an analogue multimeter
- an overview or tutorial about what an analogue or analog multimeter is, how to use it and how it works.
This test meter tutorial is split into several pages: Analogue multimeter
 DMM digital multimeter
 Basic instructions on how to use a multimeter
 Multimeter tutorial and video
 Making a multimeter voltage measurement
 How to measure current with a multimeter
 Making a multimeter resistance measurement
 Simple diode and transistor test
 Testing and fault finding a transistor circuit
A analog or analogue multimeter is one of the trusty workhorses of the electronics test industry. Analogue multimeters have been in use for very many years and sometimes go by the name VOA as a result of the fact that they measure volts, ohms and amps. These multimeters are extremely flexible and enable very many faults to be found in an electronics ciricuit.
Analogue multimeter ranges
Analogue multimeters, like digital ones have a variety of ranges. They are described in terms of Full Scale Deflection or FSD. This is the maximum that the range can read. In order to get the best reading, it is necessary to have the scale reading somewhere between about a quarter and all of the FSD. In this way the optimum accuracy and significant number of figures can be read. As a result of this meters have a variety of ranges, that may appear to be reasonably close to each other.
A typical meter may have the following ranges (note that the figures indicate the FSD):
There are several points to note from this typical analogue multimeter specification:
One of the specifications for an analogue multimeter is its sensitivity. This comes about because the meter must draw a certain amount of current from the circuit it is measuring in order for the meter to deflect. Accordingly the meter appears as another resistor placed between the points being measured. The way this is specified is in terms of a certain number of Ohms (or more usually kOhms) per volt. The figure enables the effective resistance to be calculated for any given range.
Thus if a multimeter had a sensitivity of 20 kOhms per volt, then on the range having a full scale deflection of 10 volts, it would appear as a resistance of 10 x 20 kohms, i.e. 200 kohms.
When making measurements the resistance of the meter should be at the very least ten times the resistance of the circuit being measured. As a rough guide, this can be taken to be the highest resistor value near where the meter is connected.
Normally the sensitivity of an analogue meter is much less on AC than DC. A meter with a DC sensitivity of 20 kohms per volt on DC might only have a sensitivity of 1 kohm per volt on AC.
The operation of an analogue multimeter is quite easy. With a knowledge of how to make voltage, current and resistance measurements (see the "Related Articles" on the left hand side of this page for further details) it is only necessary to know how to use the multimeter. If the meter is new then it will obviously be necessary to install any battery or batteries needed for the resistance measurements.
When using the meter it is possible to follow a number of simple steps: