Various types of electrical measuring instruments

Ammeter and voltmeter Ammeter is always connected in series with circuits, Resistance of ammeter should be low, for that number of turns in operating coil is low. Voltmeter is connected parallel with circuit. Resistance of voltmeter should be high, for that high resistance is placed series with the operating coil. To enhance the measuring capacity …

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spectrum analyser, logic probe, signature analyser, logic analyser, signal generator and distortion meter

spectrum analyser Spectrum analyser frequency range must extend well beyond the fundamental frequency of the signal (10 times of fundamental frequency). Spectrum analyzer are classified in to Swept or superheterodyne spectrum analyser, Fast Fourier Transform (FFT) analyser, Real-time analyser, Audio spectrum analyser. The more commonly used technology is the swept spectrum analyser. Swept spectrum analyser …

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Analog storage oscilloscope, digital storage oscilloscope,bridges used for measurement

Value of secondary emission ratio (SER) depends on primary electron velocity and intensity. Lower and upper stable points of SER represents erased and written conditions of CRT screen. In the absence of target voltage target will remain in lower stable point or upper stable point. For multiple target there are two guns – flood gun …

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Instrumentation and measurement, important points

Precision is a measure of reproductability in measurement. 3 types of galvanometer sensitivity – current, voltage, megohm. Current sensitivity is ratio between deflection(in mm) and current (in micro amphere). Voltage sensitivity is ratio between deflection (in mm) and voltage ( in milli volt). Megohm is numerically equal to current sensitivity. Megohm sensitivity is the megohms …

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