A cheap, simple kind of meter can be made using a string of light-emitting diodes (LEDs) or a liquid-crystal display (LCD) along with a digital scale, to indicate approximate levels of current, voltage or power. This type of meter has no moving parts to break, just like a digital meter. But it also offers the relative-reading feeling you get with an analog meter.
Figure below is an example of a bar-graph meter that is used to show the power output, in kilowatts, for a radio transmitter. It indicates 0.8 kW or 800 watts, approximately.
The chief disadvantage of the bar-graph meter is that it isn’t very accurate. For this reason it is not generally used in laboratory testing. The LED or LCD devices sometimes also flicker when the level is “between” two values given by the bars. This can be annoying to some people.