Solid State Voltmeter: Solid State Voltmeter – Figure 4.13 shows the circuit of an electronic voltmeter using an IC OpAmp 741C. This is a directly coupled very high gain amplifier. The gain of the OpAmp can be adjusted to any suitable lower value by providing appropriate resistance between its output terminal, Pin No. 6, and …
Chopper type DC Amplifier Voltmeter (Microvoltmeter): Chopper type DC Amplifier Voltmeter the dc input voltage is converted into an ac voltage, amplified by an ac amplifier and then converted back into a dc voltage proportional to the original input signal. The balanced bridge voltmeter has limitations caused by drift problems in dc amplifier. Any fluctuations …
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Transistor Voltmeter (TVM): Transistor Voltmeter – Direct coupled amplifiers are economical and hence used widely in general purpose low priced VTVM’ s. Figure 4.9 gives a simplified schematic diagram of a dc coupled amplifier with an indicating meter. The dc input is applied to a range attenuator to provide input voltage levels which can be …
DC Meter: The most commonly used dc meter is based on the fundamental principle of the motor. The motor action is produced by the flow of a small amount of current through a moving coil which is positioned in a permanent magnetic field. This basic moving system, often called the D’Arsonval movement, is also referred …