Assertion (A) : Wein bridge oscillator is generally used as a variable audio frequency oscillator Reason (R) :

Assertion (A) : Wein bridge oscillator is generally used as a variable audio frequency oscillator

Reason (R) : by using either capacitor (or) resistor in one of the arms of the bridge, the frequency of a wein bridge oscillator can be varied

(A) Both (A) & (R) are true & (R) is correct explanation of (A)

(B) Both (A) & (R) are true but (R) is not the correct explanation of (R).

(C) (A) is true but (R) is false

(D) (A) is false but (R) is true
by

1 Answer

Answer :

Assertion (A) : Wein bridge oscillator is generally used as a variable audio frequency oscillator

Reason (R) : by using either capacitor (or) resistor in one of the arms of the bridge, the frequency of a wein bridge oscillator can be varied

(A) Both (A) & (R) are true & (R) is correct explanation of (A)

(B) Both (A) & (R) are true but (R) is not the correct explanation of (R).

(C) (A) is true but (R) is false

(D) (A) is false but (R) is true

by

Related questions

When the capacitors of a Wein Bridge are replaced by inductors, the bridge becomes ___

Description : When the capacitors of a Wein Bridge are replaced by inductors, the bridge becomes ___

Last Answer : Wein Inductance Bridge

Wein bridge finds application in

Last Answer : Wein bridge finds application in Frequency determination, Harmonic distortion analyser.

Feedback factor at the frequency of oscillation of a Wien bridge oscillator is:

Description : Feedback factor at the frequency of oscillation of a Wien bridge oscillator is:  (1) 3 (2) 1/3 (3) 1/29 (4) 3/29

Last Answer : Feedback factor at the frequency of oscillation of a Wien bridge oscillator is: 1/3.

Weins bridge is used for measurement of frequency in the applied voltage waveform is measurement of

Description : Weins bridge is used for measurement of frequency in the applied voltage waveform is measurement of frequency in the applied voltage waveform is   (A)sinusoidal (B) square (C) rectangular (D) triangular

Last Answer : Weins bridge is used for measurement of frequency in the applied voltage waveform is measurement of frequency in the applied voltage waveform is sinusoidal 

The most commonly used null deflector in a power frequency ac bridge is a:

Last Answer : The most commonly used null deflector in a power frequency ac bridge is a: Vibration galvanometer.

A plot of pressure vs. temperature for a given substance showing the various phases possible for that particular substance.  a. Phase diagram  b. P-T diagram  c. Wein Diagram  d. Histogram

Description : A plot of pressure vs. temperature for a given substance showing the various phases possible for that particular substance.  a. Phase diagram  b. P-T diagram  c. Wein Diagram  d. Histogram

Last Answer : Phase diagram

The main advantage of crystal oscillator is that its output is:

Last Answer : The main advantage of crystal oscillator is that its output is: A Constant frequency range

A Wien Bridge Oscillator is suitable for

Description : A Wien Bridge Oscillator is suitable for  1. Audio frequency applications 2. Radio frequency applications 3. Very low frequency applications Which of the above frequency applications is/are correct ?

Last Answer : A Wien Bridge Oscillator is suitable for Audio frequency applications

Which of the following best describes a dip-meter? A. An SWR meter B. A counter C. A variable LC oscillator with metered feedback current D. A field strength meter

Description : Which of the following best describes a dip-meter? A. An SWR meter B. A counter C. A variable LC oscillator with metered feedback current D. A field strength meter

Last Answer : C. A variable LC oscillator with metered feedback current

Best described a dip-meter. A. A variable LC oscillator with metered feedback current B. An SWR meter C. A counter D. A field strength meter

Description : Best described a dip-meter. A. A variable LC oscillator with metered feedback current B. An SWR meter C. A counter D. A field strength meter

Last Answer : A. A variable LC oscillator with metered feedback current

Assertion `:` Generally old people have hiher blood pressure. Reason `:` Arterial diameter increases with Age.

Description : Assertion `:` Generally old people have hiher blood pressure. Reason `:` Arterial diameter increases with Age.

Last Answer : Assertion `:` Generally old people have hiher blood pressure. Reason `:` Arterial diameter increases with ... D. If both Assertion & Reason are false.

Assertion :- Disappearance of nuclear membrane is generally essential for karyokinesis Reason :- Forward movement of chromosomes is dependent on spind

Description : Assertion :- Disappearance of nuclear membrane is generally essential for karyokinesis Reason :- Forward movement of chromosomes is dependent on spind

Last Answer : Assertion :- Disappearance of nuclear membrane is generally essential for karyokinesis Reason :- Forward ... If both Assertion & Reason are false.

Assertion: In acute constipation, purgative containing magnesium salts are generally used. Reason: The osmotic effect of `Mg^(2+)` in the intestinal l

Description : Assertion: In acute constipation, purgative containing magnesium salts are generally used. Reason: The osmotic effect of `Mg^(2+)` in the intestinal l

Last Answer : Assertion: In acute constipation, purgative containing magnesium salts are generally used. Reason: The osmotic ... `Mg^(2+)` is absorbed very slowly

When an AC voltage, of variable frequency is applied to series L-C-R circuit, the current in the cirucit is the same at 4kHz. The current in the cirui

Description : When an AC voltage, of variable frequency is applied to series L-C-R circuit, the current in the cirucit is the same at 4kHz. The current in the cirui

Last Answer : When an AC voltage, of variable frequency is applied to series L-C-R circuit, the current in the cirucit ... is maximum at (x)kHz. Find the value of x

What is the local oscillator (mixer) frequency of the satellite with an uplink frequency in GHz band? A. 3500 MHz B. 4500 MHz C. 2225 MHz D. 2555 MHz

Description : What is the local oscillator (mixer) frequency of the satellite with an uplink frequency in GHz band? A. 3500 MHz B. 4500 MHz C. 2225 MHz D. 2555 MHz

Last Answer : C. 2225 MHz

When measuring a transmitter’s frequency against a suitable standard, the frequency to be measured is taken from the A. oscillator stage B. intermediate amplifier C. buffer stage D. final RF stage

Description : When measuring a transmitter’s frequency against a suitable standard, the frequency to be measured is taken from the A. oscillator stage B. intermediate amplifier C. buffer stage D. final RF stage

Last Answer : D. final RF stage

An FM receiver whose intermediate frequency is 10.7 MHz, is experiencing image channel interference from a station transmitting on 121.1 MHz. If the local oscillator is tracking above, the receiver is tuned to A. 131.8 MHz B. 110.4 MHz C. 142.5 MHz D. 99.7 MHz

Description : An FM receiver whose intermediate frequency is 10.7 MHz, is experiencing image channel interference from a station transmitting on 121.1 MHz. If the local oscillator is tracking above, the receiver is tuned to A. 131.8 MHz B. 110.4 MHz C. 142.5 MHz D. 99.7 MHz

Last Answer : D. 99.7 MHz

One of the following is a possible cause for a slow drift of frequency in a self-exited transmitter oscillator circuits resulting to a poor frequency stability. A. Loose shielding B. Heating of capacitor in the oscillator C. Poor soldered connections D. Faulty capacitor, resistor, tubes or resistors

Description : One of the following is a possible cause for a slow drift of frequency in a self-exited transmitter oscillator circuits resulting to a poor frequency stability. A. Loose shielding B. ... capacitor in the oscillator C. Poor soldered connections D. Faulty capacitor, resistor, tubes or resistors

Last Answer : B. Heating of capacitor in the oscillator

How do you eliminate radio frequency variation of an oscillator transmitter caused by its supply voltage? A. Use new power supply B. Lossen power supply shielding C. Use of regulated power supply D. Use of high capacitor in the supply circuit

Description : How do you eliminate radio frequency variation of an oscillator transmitter caused by its supply voltage? A. Use new power supply B. Lossen power supply shielding C. Use of regulated power supply D. Use of high capacitor in the supply circuit

Last Answer : C. Use of regulated power supply

One of the following is a high powered RF ac basic transmitter that has two or more stages, the oscillator stage which determines the frequency opereation and RF amplifier stage orstages that develop the high power output. The purpose of which is to develop a good frequency stability. A. Goldsmith B. MOPA C. Alexanderson D. Hartley

Description : One of the following is a high powered RF ac basic transmitter that has two or more stages, the oscillator stage which determines the frequency opereation and RF amplifier stage orstages that develop the ... to develop a good frequency stability. A. Goldsmith B. MOPA C. Alexanderson D. Hartley

Last Answer : B. MOPA

One of the following is a possible cause of an abrupt frequency variation in a self exited transmitter oscillator circuits resulting to a poor frequency stability to hold a constant frequency oscillation. A. Heating and expansion of oscillator coil B. DC and RF ac heating of resistors which cause change in values C. Heating of capacitor in the oscillatorD. Loose connections in the oscillator, amplifier, or antenna circuits.

Description : One of the following is a possible cause of an abrupt frequency variation in a self exited transmitter oscillator circuits resulting to a poor frequency stability to hold a constant frequency ... capacitor in the oscillator D. Loose connections in the oscillator, amplifier, or antenna circuits.

Last Answer : D. Loose connections in the oscillator, amplifier, or antenna circuits.

Which of the following is one of the possible causes for a slow drift of frequency in a self exited transmitter oscillator circuits resulting to a poor frequency stability? A. Poor soldered connections B. Power supply voltage changes C. Loose connections in the oscillator, amplifier, or antenna circuits D. DC and RF heating of resistors, causing then to change values.

Description : Which of the following is one of the possible causes for a slow drift of frequency in a self exited transmitter oscillator circuits resulting to a poor frequency stability? A. Poor soldered connections ... , or antenna circuits D. DC and RF heating of resistors, causing then to change values.

Last Answer : D. DC and RF heating of resistors, causing then to change values.

Refer to the deviation of the operating frequency of a crystal oscillator from its nominal value due to temperature variations. A. Drift B. Flash over C. Frequency deviation D. Deviation ratio

Description : Refer to the deviation of the operating frequency of a crystal oscillator from its nominal value due to temperature variations. A. Drift B. Flash over C. Frequency deviation D. Deviation ratio

Last Answer : A. Drift

What is the local oscillator frequency range commercial AM broadcast if it is equal to 455 KHz. A. 540 to 1600 KHz B. 0 to 1600 KHz C. 995 to 2055 KHz D. 0 to 455 KHz

Description : What is the local oscillator frequency range commercial AM broadcast if it is equal to 455 KHz. A. 540 to 1600 KHz B. 0 to 1600 KHz C. 995 to 2055 KHz D. 0 to 455 KHz

Last Answer : C. 995 to 2055 KHz

ECE Board Exam March 1996 What is the purpose of a beat frequency oscillator (BFO)? A. Aid in the reception of weak voice-modulated signals B. Generates a signal, whose frequency is the same as that of the intermediate frequency C. Generates a 1kHz note for Morse code reception D. Generates an output, whose frequency differs from that of the intermediate frequency by 1 kHz

Description : ECE Board Exam March 1996 What is the purpose of a beat frequency oscillator (BFO)? A. Aid in the reception of weak voice-modulated signals B. Generates a signal, whose frequency is the ... reception D. Generates an output, whose frequency differs from that of the intermediate frequency by 1 kHz

Last Answer : C. Generates a 1kHz note for Morse code reception

For an under damped harmonic oscillator, resonance A Occurs when excitation frequency is greater than undamped natural frequency B Occurs when excitation frequency is less than undamped natural frequency C Occurs when excitation frequency is equal to undamped natural frequency D Never occurs

Description : For an under damped harmonic oscillator, resonance A Occurs when excitation frequency is greater than undamped natural frequency B Occurs when excitation frequency is less than undamped natural frequency C Occurs when excitation frequency is equal to undamped natural frequency D Never occurs

Last Answer : C Occurs when excitation frequency is equal to undamped natural frequency

For an under damped harmonic oscillator, resonance a) occurs when excitation frequency is greater than undamped natural frequency b) occurs when excitation frequency is less than undamped natural frequency c) occurs when excitation frequency is equal to undamped natural frequency d) never occurs

Description : For an under damped harmonic oscillator, resonance a) occurs when excitation frequency is greater than undamped natural frequency b) occurs when excitation frequency is less than undamped natural frequency c) occurs when excitation frequency is equal to undamped natural frequency d) never occurs

Last Answer : c) occurs when excitation frequency is equal to undamped natural frequency

For an underdamped harmonic oscillator, resonance ______. (A) occurs when excitation frequency is greater than the undamped natural frequency (B) occurs when excitation frequency is less than the undamped natural frequency (C) occurs when excitation frequency is equal to the undamped natural frequency (D) never occurs

Description : For an underdamped harmonic oscillator, resonance ______. (A) occurs when excitation frequency is greater than the undamped natural frequency (B) occurs when excitation frequency is less than the ... ) occurs when excitation frequency is equal to the undamped natural frequency (D) never occurs

Last Answer : (C) occurs when excitation frequency is equal to the undamped natural frequency

For an under damped harmonic oscillator, resonance a) occurs when excitation frequency is greater than undamped natural frequency b) occurs when excitation frequency is less than undamped natural frequency c) occurs when excitation frequency is equal to undamped natural frequency d) never occurs

Description : For an under damped harmonic oscillator, resonance a) occurs when excitation frequency is greater than undamped natural frequency b) occurs when excitation frequency is less than undamped natural frequency c) occurs when excitation frequency is equal to undamped natural frequency d) never occurs

Last Answer : c) occurs when excitation frequency is equal to undamped natural frequency

Load regulation is a measure of a power supplies ability keep a constant output under conditions of changing A) Line voltage B) Current demand C) Temperature D) Oscillator frequency.

Description : Load regulation is a measure of a power supplies ability keep a constant output under conditions of changing A) Line voltage B) Current demand C) Temperature D) Oscillator frequency.

Last Answer : A) Line voltage

Six (6) MHz crystal oscillator has a stability of 1 part in 106. The largest frequency error expected of this crystals A) 0.06 Hz B) 0.6 Hz C) 6 Hz D) 60 Hz.

Description : Six (6) MHz crystal oscillator has a stability of 1 part in 106. The largest frequency error expected of this crystals A) 0.06 Hz B) 0.6 Hz C) 6 Hz D) 60 Hz.

Last Answer : C) 6 Hz

An oscillator that uses crystal control should be A) Frequency stable B) useful only at low frequencies C) AVFO D) none of the above.

Description : An oscillator that uses crystal control should be A) Frequency stable B) useful only at low frequencies C) AVFO D) none of the above.

Last Answer : A) Frequency stable

What transmission method uses a stable cw reference oscillator, which is locked in phase with the transmitter frequency?

Description : What transmission method uses a stable cw reference oscillator, which is locked in phase with the transmitter frequency?

Last Answer : Pulse-Doppler.

In a heterodyne-type frequency meter, what is the difference between the oscillator frequency and the unknown frequency?

Description : In a heterodyne-type frequency meter, what is the difference between the oscillator frequency and the unknown frequency?

Last Answer : Beat frequency.

What determines the frequency of a tunnel-diode oscillator?

Description : What determines the frequency of a tunnel-diode oscillator?

Last Answer : The tuned circuit or cavity frequency.

In an fm transmitter, when does an oscillator generate only a steady frequency?

Description : In an fm transmitter, when does an oscillator generate only a steady frequency?

Last Answer : When no modulation is present.

A superheterodyne radio receiver with an IF of 455KHZ is turned to 1000KHZ. Find: (i) Image frequency (ii) Local oscillator frequency

Description : A superheterodyne radio receiver with an IF of 455KHZ is turned to 1000KHZ. Find: (i) Image frequency (ii) Local oscillator frequency

Last Answer : Given Intermediate Frequency fi=455KHz Signal frequency =fs=1000KHz Local oscillator frequency fo=fs+fi  Fo=1000KHz+455KHz  =1455KHz Image frequency is the input frequency which produces the same intermediate frequency fsi=fs+2fi  =1000KHz+2*455KHz  =1910KHz 

Why should local oscillator frequency be greater than signal frequency in AM receiver? Also explain why IF has constant value?

Description : Why should local oscillator frequency be greater than signal frequency in AM receiver? Also explain why IF has constant value?

Last Answer : Reason for LO frequency to be greater than signal frequency The local oscillator frequency (f0) is made greater than signal frequency (Fs) in radio receiver: Local oscillator frequency range is 995 ... frequency of desired signal because the IF is constant and same for all the incoming RF signal.

A super heterodyne AM receiver is tuned to a station operating at 1200 KHz .Find local oscillator frequency and image frequency.

Description : A super heterodyne AM receiver is tuned to a station operating at 1200 KHz .Find local oscillator frequency and image frequency.

Last Answer : A super heterodyne AM receiver is tuned to a station operating at 1200 KHz Intermediate frequency is 455KHz. IF frequency=f0-fs Local oscillator frequency is f0=IF +fs=455K+1200K=1655kHz The image frequency which gives the same IF is f0+2*IF=2110KHz

Draw the labeled circuit of RC phase shift oscillator. State the formula for frequency of oscillator.

Description : Draw the labeled circuit of RC phase shift oscillator. State the formula for frequency of oscillator.

Last Answer : Frequency of oscillation is given by,

List two types of oscillator, which generates frequency in RF range.

Description : List two types of oscillator, which generates frequency in RF range.

Last Answer : Types of Oscillators generating frequencies in RF range: i) Hartley Oscillator ii) Colpitt’s Oscillator iii) Clapp Oscillator

In a transistor Colpitts oscillator, C1 = 0.001 µF, C2 = 0.01 µF and L = 5 µH. The frequency of oscillation in

Description : In a transistor Colpitts oscillator, C1 = 0.001 µF, C2 = 0.01 µF and L = 5 µH. The frequency of oscillation in MHz will be (a) 2.37 MHz (b) 10.00 MHz (c) 11.54 MHz (d) 9.09 MHz 

Last Answer : c

In a radio transmitter, the frequency of the crystal oscillator will be stable for a long time if the quality factor

Description : In a radio transmitter, the frequency of the crystal oscillator will be stable for a long time if the quality factor of the crystal resonator is  (a) > 100 (b) > 500 (c) > 1000 (d) > 20000

Last Answer : In a radio transmitter, the frequency of the crystal oscillator will be stable for a long time if the quality factor of the crystal resonator is  > 1000

The frequency stability of the oscillator output is maximum in _____.

Description : The frequency stability of the oscillator output is maximum in _____.   (a) Crystal oscillator (b) Phase shift oscillator (c) LC oscillator (d) Wien bridge oscillator 

Last Answer : The frequency stability of the oscillator output is maximum in Crystal oscillator. 

The crystal oscillator frequency is very stable due to

Last Answer : The crystal oscillator frequency is very stable due to High Q of the crystal.

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

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

Last Answer : In an R-C phase shift oscillator, the minimum no. of R-C networks to be connected in cascade will be 3

Assertion (A) `:` Amphibians have evolved from fishes . Reason (R ) `:` Archaeopteryx is a fossil linking fishes and amphibians `:`

Description : Assertion (A) `:` Amphibians have evolved from fishes . Reason (R ) `:` Archaeopteryx is a fossil linking fishes and amphibians `:`

Last Answer : Assertion (A) `:` Amphibians have evolved from fishes . Reason (R ) `:` Archaeopteryx is a ... false D. If both Assertion and Reason are false.

Assertion (A) : Cancer cells are virtually immortal until the body in which they reside dies. Reason`(R)`: Cancer is caused by damage to genes regulat

Description : Assertion (A) : Cancer cells are virtually immortal until the body in which they reside dies. Reason`(R)`: Cancer is caused by damage to genes regulat

Last Answer : Assertion (A) : Cancer cells are virtually immortal until the body in which they reside dies. Reason ... D. If both the assertion and reason are false

Assertion (A): Organ transplantation patients are given immunosuppressive durgs. Reason (R): Transplanted tissue has antigens which stimulate the spec

Description : Assertion (A): Organ transplantation patients are given immunosuppressive durgs. Reason (R): Transplanted tissue has antigens which stimulate the spec

Last Answer : Assertion (A): Organ transplantation patients are given immunosuppressive durgs. Reason (R): ... If both the assertion and reason are false

Assertion (A): A person who has received a cut and is bleeding needs to be given antitetanus treatment. Reason(R): Antitetanus injection provides immu

Description : Assertion (A): A person who has received a cut and is bleeding needs to be given antitetanus treatment. Reason(R): Antitetanus injection provides immu

Last Answer : Assertion (A): A person who has received a cut and is bleeding needs to be given antitetanus ... D. If both the assertion and reason are false