Welcome to electronics2electrical.com here you can ask questions related to electrical, electronics, mechanical, telecommunication, instrumentation, computer, mathematics, physics etc. Be respectful to all the members. Do not copy and paste the answers from other websites which have copyright content. While asking question give full details about it, Please login or register to continue.

10 views
in Instrumentation and control by
A Voltage Controlled Oscillator (VCO) is an instrument : - a) whose frequency is dependent upon the amplitude of input signal b) whose frequency is independent upon the amplitude of input signal c) whose frequency is dependent upon the frequency of input signal d) none of the above

Your answer

Thanks for your contribution. Feel free to answer this question. Please avoid short answer. Your answer is most welcome. Be genuine.

Upload image or document:

Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.

1 Answer

0 votes
by

A Voltage Controlled Oscillator (VCO) is an instrument : - whose frequency is dependent upon the amplitude of input signal

Related questions

0 answers 138 views

In PLL 565, timing components of VCO are 10 kOhm and 0.01 microfarad. Supply voltage is +10V and -10V. The voltage to frequency conversion factor of VCO is about  A) 250 Hz/V B) 500 Hz/V C) 750 Hz/V D) 1000 Hz/V

asked Apr 9, 2018 in Electronics Engineering by Shimroz123
1 answer 18 views

The input voltage to an OP AMP is a large voltage step. The output is an exponential waveform that changes to 0.25 V in 0.1µs (microsecond). The slew rate of the OP AMP is : -  a) 5V/µs b) 2.5 V/ µs c) 3V/µs d) 4.5V/ µs

asked Apr 10, 2018 in Instrumentation and control by Shimroz123
1 answer 8 views

In a three phase controlled bridge rectifier with an increase of overlap angles the output dc voltage

asked May 23, 2018 in Power Electronic Controlled Drives by Shimroz123
1 answer 10 views

Torque/weight ratio of an instrument indicates   (a) Selectivity (b) Accuracy (c) Fidelity (d) Sensitivity

asked May 13, 2018 in Instrumentation and control by Shimroz123
1 answer 12 views

An amplifier has a voltage gain of 50; this gain in dB will be (A) 34 dB (B) 68 dB (C) 41 dB (D) 14 dB 

asked Apr 23, 2018 in Instrumentation and control by Shimroz123
0 answers 72 views

In a digital voltmeter, the oscillator frequency is 400 kHz, the ramp voltage falls from 8V to 0V in 20 m sec. The number of pulses counted by the counter is (a) 800 (b) 2000 (c) 4000 (d) 8000

asked May 25, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 20 views

The sweep width in CRO is controlled by: -  a) Horizontal Gain Control b) Vertical Gain Control c) Accelerating-Anode Potential Control d) Focussing Anode Potential Control

asked Apr 10, 2018 in Instrumentation and control by Shimroz123
1 answer 11 views

An oscillator that uses a tapped coil to obtain the feedback is called: a. A Hartley circuit b. A Pierce circuit c. A multivibrator d. A negative feedback circuit

asked Aug 31, 2018 by Shimroz123
1 answer 22 views

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. Shape of pole shoe for the horse shoe magnet   Select the correct answer using the code given below:   (a) Only 1 and 3 (b) Only 2 and 4 (c) Only 2 and 3 (d) Only 1 and 4 

asked May 13, 2018 in Instrumentation and control by Shimroz123
1 answer 101 views

If a voltage-controlled bus is treated as load bus, then which one of the following limits would be violated?   (a) Active power (b) Reactive power (c) Voltage (d) Phase angle 

asked May 13, 2018 in Power system by Shimroz123
1 answer 38 views

The speed of a three-phase induction motor is controlled by variable voltage variable frequency control (i.e. keeping V/f constant). As the frequency is reduced, the slip at maximum torque  (1) Decreases (2) Increases (3) Remains constant (4) None of the above

asked May 1, 2018 in Electrical Machine by Shimroz123
1 answer 26 views

A current controlled voltage source is equivalent to :  (A) series voltage feed -back amplifier (B) shunt current feed -back amplifier (C) shunt voltage feed -back amplifier (D) series current feed -back amplifier

asked Apr 30, 2018 in Electrical Engineering by Shimroz123
1 answer 156 views

For a 15-bus power system with 3 voltage controlled buses, the size of Jacobian matrix is

asked Apr 27, 2018 in Switchgear And Protection by Shimroz123
1 answer 14 views

A solar cell of 350 V is feeding power to an ac supply of 440 V, 50 Hz through a 3-phase fully controlled bridge converter. A large inductance is connected in the dc circuit to maintain the dc current at 20 A. If the solar cell resistance is 0.5 Ohm ,then each thyristor will be reverse biased for a period of  (A) 125o (B) 120o (C) 60o (D) 55o

asked May 18, 2018 in Power electronics converters by Shimroz123
1 answer 15 views

A single-phase fully controlled thyristor bridge ac-dc converter is operating at a firing angle of 25o and an overlap angle of 10o with constant dc output current of 20 A. The fundamental power factor (displacement factor) at input ac mains is  (A) 0.78 (B) 0.827 (C) 0.866 (D) 0.9

asked May 18, 2018 in Power electronics converters by Shimroz123
1 answer 47 views

The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is 220 V. With the potential coil connected on the load side, the meter indicates 100 W. Approximate percentage error due to wattmeter connection is (A) 11% (B) 9% (C) 1.1% (D) 3%

asked Apr 25, 2018 in Instrumentation and control by Shimroz123
1 answer 12 views

The polarity of induced voltage while a field is collapsing is : - a) independent of the force creating the field b) opposite to the force creating c) the field identical to the force creating d) the field present only if the force is stationary

asked Apr 14, 2018 in Instrumentation and control by Shimroz123
1 answer 15 views

A Pyrheliometer is an instrument to measure :  (A) temperature of solar photovoltaic cell  (B) intensity of direct solar radiation at normal incidence  (C) intensity of indirect solar radiation  (D) efficiency of a solar photovoltaic cell

asked Apr 29, 2018 in Electrical Measurements and Instrumentation by Shimroz123
0 answers 54 views

A single phase, half-wave, controlled rectifier has 400 sin (314 t) as the input voltage and R as the load. For a firing angle of 60° for the SCR, the average output voltage is   (a) 240/π (b) 400/π (c) 300/π (d) 200/π 

asked Apr 10, 2018 in Electrical Engineering by Shimroz123
1 answer 5 views
1 answer 11 views

The output of an AND gate with three inputs, A, B and C, is HIGH when __________. a) A=1,B=1,C=0 b) A= 0,B= 0,C= 0 ' c) A=1,B=1,C=1 d) A=1,B= 0,C= 1

asked Apr 14, 2018 in Instrumentation and control by Shimroz123
1 answer 30 views

The Q factor of a coil at resonant frequency 1.5 MHz of an RLC series circuit is 150. The Bandwidth is : - a) 225 MHz b) 1.06 MHz c) 10 KHz d) 10 MHz

asked Apr 14, 2018 in Instrumentation and control by Shimroz123
1 answer 68 views

An aquadog is used in a 'CRO' to collect -  a) Secondary emission electrons b) Primary emission electrons c) Both Primary and Secondary emission electrons d) None of the above

asked Apr 10, 2018 in Instrumentation and control by Shimroz123
1 answer 22 views

 In an electronic ohmmeter an op -amp is used as a: -  a) sommer b) multiplier c) buffer amplifier d) integrator

asked Apr 10, 2018 in Instrumentation and control by Shimroz123
1 answer 37 views

In voltage source converter based HVDC transmission system the active power is controlled by changing (A) phase angle of the converter ac input voltage (B) supply frequency of the converter ac input voltage (C) magnitude of the converter ac input voltage (D) DC voltage at the inverter terminals

asked Apr 28, 2018 in High voltage engineering by Shimroz123
1 answer 18 views

A single phase full-wave half-controlled bridge converter feeds an inductive load. The two SCRs in the converter are connected to a common DC bus. The converter has to have a freewheeling diode.  (A) because the converter inherently does not provide for free-wheeling (B) because the converter does not provide for free-wheeling for high ... the AC supply (D) or else if a gate pulse to one of the SCRs is missed, it will subsequently cause a high load current in the other SCR.

asked May 18, 2018 in Power electronics converters by Shimroz123
0 answers 14 views

 A single phase full -wave half controlled bridge converter feeds an inductive load: The two SCRs in the converter are connected to a common DC bus. The converter has to have a free wheeling diode (A) Because the converter inherently does not provide for free wheeling (B) Because the converter does not provide for free wheeling for high ... the AC supply (D) Or else if a gate pulse to one of the SCRs is missed, it will subsequently cause a high load current in the other SCR

asked Apr 14, 2018 in Electrical Engineering by Shimroz123
0 answers 16 views

A dynamometer type wattmeter with its voltage coil connected across the load side of instrument reads 250 W. If the load voltage be 200 V, what power is being taken by load? The voltage coil has resistance of 2000 Ω. (1) 200 W (2) 215W (3) 230 W /(4) 245 W

asked Apr 11, 2018 in Electrical Engineering by Shimroz123
1 answer 19 views

With a 12 V supply, a silicon diode, and a 370 - ohm resistor in series, what voltage will be dropped across the diode? a) 0.3V b) 0.7V c) 0.9V d) 1.4V

asked Apr 14, 2018 in Instrumentation and control by Shimroz123
1 answer 16 views

Tachometer works essentially as a generator with output voltage proportional to magnitude of the : - a) Angular Velocity of the shaft b) Torque of the shaft c) Temperature of the shaft d) Back Lash of the shaft

asked Apr 14, 2018 in Instrumentation and control by Shimroz123
0 answers 119 views

What is the order of the characteristic equation of an armature controlled DC motor?  (A) First order equation (B) Second order equation (C) Zero order equation (D) Third order equation 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
2 answers 75 views

What type of instrument is used to measure dc voltage of the order 5 volts? (A) moving iron type (B) electro-static type (C) moving coil type (D) all of these

asked Apr 23, 2018 in Electronics Engineering by Shimroz123
1 answer 23 views

 In the case of an instrument reading of 8.3 V with a 0 to 150 voltmeter having a guaranteed accuracy of 1% full scale reading, the percentage limiting error is   (A) 1.810% (B) 0.181% (C)12.45% (D) 0.0018%

asked May 17, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 13 views

An analog voltmeter has a sensitivity of 10kΩ/volt. The galvanometer used in constructing the instrument will produce a full scale deflection when the current passed through it is  (a) 10 mA (b) 20 mA (c) 50 mA (d) 100 μA

asked May 15, 2018 in Digital Instrumentation by Shimroz123
1 answer 17 views

A PMMC instrument has FSD of 100 μA and a coil resistance of 1 kΩ. To convert the instrument into an ammeter with full scale deflection of 100 mA, the required shunt resistance is (A) 1 Ω (B) 1.001 Ω (C) 0.5 Ω (D) 10 Ω

asked Apr 28, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 14 views

In an R-C phase shift oscillator, the minimum no. of R-C networks to be connected in cascade will be -

asked May 8, 2018 in Electrical Engineering by Shimroz123
1 answer 23 views

A digital voltmeter uses an A/D converter which needs a start pulse, uses an analog comparator and has a relatively fixed conversion time independent of the applied voltage. The A/D converter is : -  a) Successive Approximation Converter .b) Digital Ramp Converter c) Digital Slope Converter d) All the above

asked Apr 10, 2018 in Instrumentation and control by Shimroz123
5 answers 202 views
0 answers 15 views

The moving system of an indicating type of electrical instrument is subjected to (a) a deflecting torque (b) a controlling torque (c) a damping torque (d) All of the above

asked May 26, 2018 in Electrical Measurements and Instrumentation by Shimroz123

Welcome to electronics2electrical.com here you can ask questions related to electrical, electronics, mechanical, telecommunication, instrumentation, computer, mathematics, physics etc.
Be respectful to all the members. Do not copy and paste the answers from other websites which have copyright content. While asking question give full details about it.

Categories

Most popular tags

power motor dc circuit transformer voltage current used system phase resistance factor synchronous load ac energy induction electric generator series frequency between speed capacitor use electrical meter line difference control type mosfet transmission magnetic plant high single instrument bjt unit source advantages function diode and machine winding field define torque parallel amplifier supply shunt thyristor motors electricity arduino maximum time relay armature problem value on transformers types coil diagram state flow ratio material three formula starting direction theorem method emf operating efficiency digital wave microprocessor test instruments inductance loss measure operation connected signal low applications effect single-phase network temperature working constant losses different law wattmeter measuring compare controlled breaker drive device logic rc full switch flux wire resistivity disadvantages free of materials machines angle force converter conductor transistor gain open protection scr core measurement number bridge principle generators reactance circuits negative the friction iron loop short pole battery conservation steam resistors hysteresis computer using analog lines secondary station gate a rectifier inverter linear induced relays nuclear capacitance basic characteristics design direct work rotor electronics ammeter forces diesel damping rlc connection factors capacitors minimum insulation moving regulation running self systems air fault range main stability quality starter igbt eddy alternator ideal rl average 3-phase plants arc thermal error fuzzy biasing dielectric pressure balanced superposition errors copper rotation feedback impedance measured electronic electrons charge inductive transfer explain start off back curve over solar is three-phase tariff locomotive peak bias zener engineering commutator surge conductors rating universal potentiometer density permanent mechanical transducer capacity memory adc excitation two fuse pure harmonics application semiconductor inductor internal pmmc reaction welding resonance traction permeability breakers rms designed electromagnetic si generation brushes switching capacitive shaded rate 1 distribution resistor methods delta star oscillator reluctance simplification algebra 8085 boolean weston dynamometer insulating strength installation definition fuel heating earth units

8,560 questions

7,160 answers

135 comments

3,090 users

...