Equation
Ʈ= B*A*I*N
Where r= torque Newton. Meter
B = flux density in the air gap. Wb/m2
A = effective coil area (m)
N= number of turns of wire of the coil
Description : Derive the relation for deflection torque in PMMC instrument.
Last Answer : Ans: The length of coil be l meter and width of coil be d meter. Assume I is the current flowing in the ciol having N turns. Assume B as the flux density in the air gap then F=BIL ... a direct indication of the current in the coil. The pointer deflection can therefore be used to measure current.
Description : List two advantages of PMMC instrument.
Last Answer : 1. It has uniform scale. 2. Power consumption is low 3. It can be obtained in wide ranges. 4. High sensitivity & accuracy 5. It is unaffected by external magnetic field. 6. Additional damping device not required. 7. Hysteresis problem is not there.
Description : Draw and explain block diagram of Horizontal deflection system.
Last Answer : Trigger circuit: A trigger circuit is used to convert the incoming signal into trigger pulses, so that the input signal and the sweep frequency can be synchronized. The trigger circuit is ... before it is applied to the horizontal section. The block consists of a push- pull amplifier
Description : Draw the construction and explain working principle of PMMC instruments
Last Answer : Working: When current passes through the coil a deflecting torque is produced. This deflecting torque is produced due to interaction between magnetic field produced by permanent magnet ... equilibrium; this is possible only when the controlling torque becomes equal to the deflecting torque
Description : Draw PMMC meter movement and describe it.
Last Answer : Working principle of PMMC: 1. The working principle of PMMC is based on basic meter movement known as D'Arsonval principle stated as when current passes through the coil ... controlling torque becomes equal to deflecting torque then pointer attached with scale become stable at equilibrium.
Description : Draw and describe horizontal deflection system in CRO
Last Answer : Block Diagram: Explanation: Input from vertical amplifier is given to Horizontal system. Trigger circuit: a. A trigger circuit is used to convert the incoming signal into trigger ... : Horizontal amplifier amplifies the signal & passes the signal to horizontal plates of CRT.
Description : Explain vertical deflection subsystem with neat diagram.
Last Answer : vertical deflection subsystem The main function of the vertical deflection system is to provide an amplified signal of prope r level toderive the vertical deflection plates without any ... suppression, reduced no nlinear effects because none of the plates are at ground potential.
Description : Sketch Block diagram of vertical deflection system used in CRO.
Last Answer : Block diagram of vertical deflection system used in CRO
Description : Explain D’Arsonal PMMC movement in detail.
Last Answer : OR Working: When current passes through the coil a deflecting torque is produced. This deflecting torque is produced due to interaction between magnetic field produced by permanent ... equilibrium; this is possible only when the controlling torque becomes equal to the deflecting torque.
Description : Draw block diagram of DMM. State its advantages.
Last Answer : Advantages of DMM: 1. DMM provides numerical readouts that eliminate observational errors. Thus providing better readability. 2. DMM offers better accuracy and versatility as compared to ... memory devices for further computations. 5. The decreased size of DMM increases the portability
Description : Draw block diagram of spectrum analyser, State applications of spectrum analyser.
Last Answer : Block Diagram: Applications: 1. Spectrum analyzer is a very important item of test equipment for someone designing or repairing electronic equipment that uses radio frequency signals. 2. Its ... of the dominant frequency within a signal 8. Used to measure the properties of RF devices
Description : Define wave analyser and state its need, Draw the block diagram of it.
Last Answer : Wave analyzer:- Wave analyzer is an instrument which is used to measure the magnitude of the various harmonics of a complex waveform. It is an instrument that is designed to measure the relative amplitudes ... distortion and the system signal to noise ratio. Block Diagram of Wave analyser
Description : Draw block diagram of DSO . State applications of DSO
Last Answer : Applications of DSO : 1. It can be used to measure both AC and DC voltages and currents. It can also calculate RMS value, peak value, peak to peak value etc. 2. It ... . 5. It can be used to determine the modulation characteristics and detect the standing waves of transmission lines.
Description : Draw block diagram of successive approximation digital voltmeter. State its two advantages and two disadvantages
Last Answer : Block diagram Or Advantages: o It is economical method of analog to digital conversion. o The resolution is up to 5 important digits are obtained. Disadvantages: o ... depends on which type of switches are used. o The conversion time required for digital to analog converter.
Description : Draw block diagram of frequency meter and state it’s principle of operation
Last Answer : Block diagram Principle The signal may be amplified before being applied to the Schmitt trigger. The Schmitt trigger converts the input signal into a square wave with fast rise and fall times, ... time interval between start and stop gate then, frequency of unknown signalis, f = N / t
Description : Draw block diagram of digital frequency meter in time mode and describe its operation.
Last Answer : OR Operation: The input signal is amplified and converted to a square wave by a Schmitt Trigger circuit. In this diagram the square wave is differentiated and clipped to ... thereby closing it. The decimal counter and display unit output correspond to the number of input pulses.
Description : What is LCR meter? Draw digital LCR –Q meter block diagram.
Last Answer : An LCR meter is a type of electronic test equipment used to measure the inductance (L), capacitance (C), and resistance (R) of an electronic component. Block diagram digital LCR –Q meter
Description : Draw block diagram of distortion factor meter and explain its operation.
Last Answer : Block Diagram Operation This meter consist following four sections 1. Impedance converter along with input circuit 2. Rejection amplifier 3. Metering circuit 4. Power circuit 1. ... of the total input voltage. 4. The power supply unit provides the supply for proper operation
Description : Draw block diagram of RF signal generator and explain its operation.
Last Answer : RF signal generator contains three other main sections: 1.OSCILLATOR CIRCUIT, 2. MODULATOR, 3. OUTPUT CONTROL CIRCUIT. The modulator modulates the RF signal of the ... . Metal shielding surrounds the unit to prevent signals from the oscillator from affecting the circuit under test
Description : Draw block diagram of function generator and list two specifications of it.
Last Answer : Specifications: 1. Output- Square wave , sine wave, Triangular, TTL pulse 2. Frequency Ranges- 0.1 Hz to 11 MHz, up/down range switchable in eight decade steps 3. Dial Range-1 to 11 calibrated 0.1 to 1 uncalibrated 4. Pulse and Ramp Aspect Ratio-95:5
Description : Draw the basic block diagram of single trace CRO and describe the function of delay line.
Last Answer : Function of Delay line: This block is used to delay the signal for a period of time in the vertical section of CRT. The input signal is not applied directly to the vertical plates because the part ... when the delay time is not used. Therefore, the input signal is delayed by a period of time.
Description : Draw block diagram of digital LCR –Q meter and explain its working.
Last Answer : Block diagram Working The output of LCR-Q meter is given to current to voltage converter, AC amplifier or DC amplifer depending upon position of switch Current to voltage ... /D converter. A/D converter converts analog signal into digital output andfinaaly displayed on display.
Description : Draw block diagram of Dual slope integrating voltmeter and also draw waveform for voltage V/s time.
Last Answer : Block diagram
Description : Sketch block diagram of pattern generator and draw any four test patterns
Last Answer : Block Diagram of Pattern Generator: Test patterns of Pattern Generator:
Description : Draw and explain construction diagram of average responding voltmeter.
Last Answer : Explain: The basic construction of average responding voltmeter is shown in above fig. at the input side of an unknown voltage to be measured is applied. The blocking capacitor is used to ... is connected in the bridge circuit. The bridge circuit consists of two diodes and two capacitors.
Description : Draw block diagram of AF sine and square wave generator and explain its working
Last Answer : The AF signal generator, which generates either sine wave or square wave in the range of audio frequencies based on the requirement is called AF Sine and Square wave generator. Its block diagram is shown ... can be used to produce either AF sine wave or AF square wave based on the requirement.
Description : Draw the circuit diagram of multi range AC voltmeter and describe its working
Last Answer : The above circuit looks like a multi range AC voltmeter. We know that, we will get AC voltmeter just by placing rectifier in series (cascade) with DC voltmeter. The above circuit was created ... any two points of an electric circuit, by connecting the switch, S to the desired voltage range.
Description : Draw block diagram of digital storage oscilloscope.
Last Answer : block diagram of digital storage oscilloscope.
Description : Draw labelled diagram of CRT.
Last Answer : labelled diagram of CRT:
Description : Draw the circuit diagram of DC signal conditioning circuit.
Last Answer : Circuit
Description : Draw the block diagram of function generator and explain its working.
Last Answer : Principle of operation of function generator: Function generator operates to produce different waveforms such as sine, square, triangular of adjustable frequency which is used to test ... whose frequency is determined by the magnitude of current supplied by constant current sources.
Description : Draw and explain the block diagram of DAS.
Last Answer : Data acquisition is the process of sampling signals that measure real world physical conditions and converting the resulting samples into digital numeric values that can be manipulated by ... controlled by software programs developed using various general purpose programming languages.
Description : Draw and describe the constructional diagram of LVDT.
Last Answer : Construction of LVDT: A differential transducer consists of a primary winding and two secondary winding. The windings are arranged concentrically and next to each other. They are wound over a ... winding and core varies the coupling between it and two secondary windings. E0=E1-E2
Description : Draw the block diagram of instrumentation system and explain function of each block.
Last Answer : Functions of each block: Primary sensing element: This first receives energy from the measured medium and produces an output depending on measured quantity. Variable conversion element: Converts ... indication of a pointer moving a scale or the recording of a pen Moving over chart.
Description : Draw block diagram of CRO and explain function of each block of it.
Last Answer : The functions of various blocks are: 1) CRT: This is cathode ray tube which emits electrons that strike phosphor screen internally to provide visual display of signal. 2) VERTICAL AMPLIFIER ... are two power supplies a high voltage supply for CRT & low voltage supply for all circuits.
Description : Which of the following factors limit the deflection of the pointer of a PMMC instrument of about 90o? 1. Its damping mechanism 2. Linearity of magnetic field in which the coil moves 3. Control spring arrangement 4. ... Only 1 and 3 (b) Only 2 and 4 (c) Only 2 and 3 (d) Only 1 and 4
Last Answer : Which of the following factors limit the deflection of the pointer of a PMMC instrument of about 90o? 1. Its damping mechanism 2. Linearity of magnetic field in which the coil moves 3. Control spring arrangement 4. ... Only 1 and 3 (b) Only 2 and 4 (c) Only 2 and 3 (d) Only 1 and 4
Description : State the advantages of Digital instrument.
Last Answer : 1. They are having high input impedance, so there is no loading effect 2. They are having higher accuracy 3. An unambiguous reading is obtained 4. The output can be interfaced with external equipment 5. They are available in smaller size
Description : Draw and state how Aryton shunt type DC ammeter . State advantage of using Aryton shunt.
Last Answer : OR The Aryton shunt eliminates the possibility of having the meter in the circuit without a shunt. This advantage is gained at the price of slightly higher overall Aryton shunt ammeter. In this ... between shunts. 3. Another advantage is that it may be used as a wide range ammeter.
Description : Draw the sketch of electromagnetic flow meter and explain it. State advantages, disadvantages and applications of it.
Last Answer : Diagram: Explanation: Electromagnetic flow meters works based on Faraday's Law of Electromagnetic Induction. According to this principle, when a conductive medium passes through a magnetic ... water, chilled water. Used for flow measurement of Corrosive liquids, slurries and pastes.
Description : Define: (i) Absolute Instrument (ii) Secondary Instrument
Last Answer : i)Absolute Instrument:An instrument whose calibration can be determined by means of physical measurements on the instrument. ii)Secondary Instrument:Secondary instruments are those, in which the ... instruments, only when they have been pre-calibrated by comparison with an absolute instrument.
Description : Suggest instrument to measure unknown frequency above 5 MHz and store result. Justify it.
Last Answer : For measurement of frequency CRO, DSO SPECTRUM ANALYZER & FREQUENCY COUNTER can be used. In above specification we can used CRO & DSO for measurement, but the data has to be stored so we ... width or higher bandwidth can be used. Because DSO has measurement facility as well as storage facility.
Description : Sketch block diagram of single trace CRO. State function of delay line.
Description : Compare CRO and DSO. State the formula for phase measurement using CRO with necessary diagram.
Last Answer : CRO DSO Directly reads analog voltage and displays it on screen. It reads the analog voltage and converts it into digital form before being displayed on the screen. ... algorithms available and ported on microprocessor which can operate on stored samples of input voltage.
Description : Explain Piezo-electric transducer with diagram. State its applications, advantages and disadvantages.
Last Answer : Explanation: Principle of operation: When a pressure or force or vibration applied to the crystalline material like quartz crystal or crystalline substances then an e.m.f. is generated across the ... destructive test (NDT) equipment's 4) Piezoelectric materials are use in ultrasonic transducers.
Description : Draw Q meter circuit of series connection and explain it.
Last Answer : Q meter circuit of series connection OR Explanation The Q meter works on series resonant. The resonance is the condition exists in the circuit when their inductance and capacitance reactance are ... . Hence E=Q Ec so ,the voltmeter is calibrated for finding the value of Q factor.
Description : Draw the construction of CRT. Write two materials used for CRT display screen.
Last Answer : Two materials used for CRT display screen: The role of this part is to display where the electrons are hitting the CRT. It is a screen coated with a material that emits light when struck by electrons. Zinc sulphide or Phosphorus are two commonly used materials.
Description : Draw and describe general Data acquisition system .
Last Answer : Data acquisition is the process of sampling signals that measure real world physical conditions and converting the resulting samples into digital numeric values that can be manipulated ... are usually controlled by software programs developed using various general purpose programming languages
Description : Explain the concept of single beam dual trace CRO with its block diagram.
Last Answer : Diagram: Explanation: The single beam dual trace CRO consists of one electron gun, an electronic switch which switches the two signals to a single vertical amplifier and a single pair of ... Amplifier are identical & have the same delay time, accurate X-Y measurements can be taken.
Description : Explain block diagram of distortion factor meter and explain how it operates
Last Answer : Fig. Distortion factor meter Working : Initially the switch S is kept at position 1. The attenuator gets excluded and the bridge T network is adjusted for full suppression of ... is obtained on the meter. Thus the total rms distortion is indicated by the reading of attenuator.
Description : Explain function of each block of logic analyzer with proper block diagram
Last Answer : Explanation: A logic analyser is an electronic instrument that captures and displays multiple signals from a digital system or digital circuit. The normal oscilloscope deals with time domain, spectrum ... When the memory receives a trigger signal, it sends the samples to a CRT display.
