{"id":24157,"date":"2020-02-24T16:54:26","date_gmt":"2020-02-24T11:24:26","guid":{"rendered":"https:\/\/kseebsolutions.guru\/?p=24157"},"modified":"2021-07-02T15:24:31","modified_gmt":"2021-07-02T09:54:31","slug":"2nd-puc-electronics-question-bank-chapter-6","status":"publish","type":"post","link":"https:\/\/kseebsolutions.guru\/2nd-puc-electronics-question-bank-chapter-6\/","title":{"rendered":"2nd PUC Electronics Question Bank Chapter 6 Oscillators"},"content":{"rendered":"

Students can Download 2nd PUC Electronics Chapter 6 Oscillators Questions and Answers, Notes Pdf, 2nd PUC Electronics Question Bank with Answers<\/a>\u00a0helps you to revise the complete Karnataka State Board Syllabus and score more marks in your examinations.<\/p>\n

Karnataka 2nd PUC Electronics Question Bank Chapter 6 Oscillators<\/h2>\n

2nd PUC Electronics Oscillators One Mark Questions and Answers<\/h3>\n

Question 1.
\nWhat is a positive feedback?
\nAnswer:
\nThe process of applying a portion of the output in phase with the input is called positive feedback.<\/p>\n

Question 2.
\nWhat is an oscillator?
\nAnswer:
\nOscillator is a circuit that converts DC energy into an AC energy of desired frequency.<\/p>\n

Question 3.
\nWhat are sinusoidal oscillators?
\nAnswer:
\nOscillators that produce sinusoidal waveforms are called sinusoidal oscillators.<\/p>\n

Question 4.
\nWhat are non-sinusoidal or relaxation oscillators?
\nAnswer:
\nOscillators that produce non-sinusoidal waves like triangular wave, square wave or saw tooth waves are called non-sinusoidal oscillators.<\/p>\n

\"2nd<\/p>\n

Question 5.
\nWhat are damped oscillations?
\nAnswer:
\nDamped oscillations are electrical oscillations whose amplitude keeps on decreasing with time but frequency remains a constant.<\/p>\n

Question 6.
\nWhat are undamped oscillations?
\nAnswer:
\nUndamped oscillations are electrical oscillations whose amplitude remains constant with respect to time.<\/p>\n

Question 7.
\nWrite the expression for the voltage gain of a positive feedback amplifier.
\nAnswer:
\nVoltage gain with positive feedback,
\n\\(A_{ f }=\\frac { A }{ 1-A\\beta }\\)<\/p>\n

Question 8.
\nDraw the basic block diagram of an oscillator.
\nAnswer:
\n\"2nd<\/p>\n

Question 9.
\nWhat is a tank circuit?
\nAnswer:
\nTank circuit or oscillatory circuit is a circuit that produces electrical oscillations of any desired frequency.<\/p>\n

Question 10.
\nWhat should be value of loop gain to start oscillations?
\nAnswer:
\nThe loop gain Ap should be greater than 1 to start the oscillations.<\/p>\n

Question 11.
\nWhat should be the value of loop gain for sustained oscillations?
\nAnswer:
\nThe loop gain Ap should be equal to 1.<\/p>\n

\"2nd<\/p>\n

Question 12.
\nHow many RC branches are required for a phase shift oscillator?
\nAnswer:
\nThree.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 ‘<\/p>\n

Question 13.
\nWhat is the amount of phase shift in each RC section of a phase shift oscillator?
\nAnswer:
\n60\u00b0.<\/p>\n

Question 14.
\nWrite the expression for frequency of oscillation of a Wein bridge oscillator.
\nAnswer:
\nFrequency,
\n\\(\\mathrm{f}=\\frac{1}{2 \\pi \\mathrm{RC}}\\)<\/p>\n

Question 15.
\nWrite the expression for frequency of oscillation of an RC phase shift oscillator.
\nAnswer:
\n\\({ f }=\\frac { 1 }{ 2\\pi \\sqrt { 6 } RC } \\quad { or\\quad }{ f }=\\frac { 0.065 }{ { RC } } \\)<\/p>\n

Question 16.
\nWrite the expression for the frequency of osillations of a Collpitts oscillator
\nAnswer:
\nFrequency \\({ f }=\\frac { 1 }{ 2\\pi \\sqrt { { LC }_{ s } } } { where\\quad }{ C }_{ s }=\\frac { { C }_{ 1 }{ C }_{ 2 } }{ { C }_{ 1 }+{ C }_{ 2 } } \\)<\/p>\n

Question 17.
\nWrite the expression for the frequency of oscillation of a Hartley oscillator.
\nAnswer:
\nFrequency \\({ f }=\\frac { 1 }{ 2\\pi \\sqrt { { LC }_{ s } } } \\) where L = L1<\/sub> + L2<\/sub><\/p>\n

Question 18.
\nWrite the expression for frequency of oscillation of a crystal oscillator.
\nAnswer:
\nFrequency \\({ f }=\\frac { 1 }{ 2\\pi \\sqrt { { LC }_{ s } } } \\)<\/p>\n

Question 19.
\nDoes the bridge circuit produce any phase shift in a Wein bridge oscillator?
\nAnswer:
\nNo. The bridge circuit does not produce any phase shift.<\/p>\n

\"2nd<\/p>\n

Question 20.
\nWrite the expression for the feedback factor of colpitts oscillator.
\nAnswer:
\nFeedback factor, \\(\\beta=\\frac{C_{1}}{C_{2}}\\)<\/p>\n

Question 21.
\nWrite the expression for the feedback factor of Hartley oscillator.
\nAnswer:
\nFeedback factor, \\(\\beta=\\frac{L_{2}}{L_{1}}\\)<\/p>\n

Question 22.
\nWrite the expression for the feedback factor of phase shift oscillator.
\nAnswer:
\nFeedback factor, \\(\\beta=\\frac{R_{i}}{R_{f}}=\\frac{1}{29}\\)<\/p>\n

Question 23.
\nWrite the expression for feedback factor of wein bridge oscillator.
\nAnswer:
\nFeedback factor, \\(\\beta=\\frac{1}{3}\\)<\/p>\n

Question 24.
\nMention the principle used in crystal oscillator.
\nAnswer:
\nPiezo-electric effect.<\/p>\n

Question 25.
\nWhat is the type of feedback used in Colpitts oscillator?
\nAnswer:
\nCapacitive feedback.<\/p>\n

\"2nd<\/p>\n

Question 26.
\nWhat is the type of feedback used in Hartley oscillator?
\nAnswer:
\nInductive feedback.<\/p>\n

Question 27.
\nDraw the symbol of crystal.
\nAnswer:
\n\"2nd<\/p>\n

Question 28.
\nDraw the pin diagram of 555 timer
\nAnswer:
\n\"2nd<\/p>\n

2nd PUC Electronics Oscillators Two Marks Questions and Answers<\/h3>\n

Question 1.
\nDistinguish between sinusoidal and relaxation oscillators.
\nAnswer:
\nSinusoidal oscillators produce sinusoidal wave forms where as relaxation oscillators produce non-sinusoidal wave forms like triangular wave, square wave or rectangular wave.<\/p>\n

\"2nd<\/p>\n

Question 2.
\nDistinguish between damped and undamped oscillations.
\nAnswer:
\nDamped osillations are the electrical oscillations whose amplitude goes on decreasing with respect to time. Undamped oscillations are electrical oscillations whose amplitude remains a constant.<\/p>\n

Question 3.
\nExplain the conditions of Barkhaussan criterion.
\nAnswer:<\/p>\n

    \n
  • The total phase shift around the closed loop should be 0\u00b0 or 360\u00b0.<\/li>\n
  • The magnitude of product of the open loop gain of the amplifier (A) and feedback ratio (P) is unity. Ie, | A\u03b2 |= 1 .<\/li>\n<\/ul>\n

    Question 4.
    \nDraw the circuit diagram of Hartley oscillator.
    \nAnswer:
    \n\"2nd<\/p>\n

    Question 5.
    \nDraw the circuit diagram of a Colpitts oscillator.
    \nAnswer:
    \n\"2nd<\/p>\n

    Question 6.
    \nDraw the circuit diagram of RC phase shift oscillator.
    \nAnswer:
    \n\"2nd<\/p>\n

    Question 7.
    \nDraw the circuit diagram of Wein bridge oscillator.
    \nAnswer:
    \n\"2nd
    \nVoltage gain A = \\(1+\\frac{\\mathrm{R}_{3}}{\\mathrm{R}_{4}}=3\\)<\/p>\n

    Question 8.
    \nDraw the circuit diagram of a crystal oscillator.
    \nAnswer:
    \n\"2nd<\/p>\n

    Question 9.
    \nWrite any two applications of Hartley oscillator.
    \nAnswer:
    \nHartley oscillator is used in<\/p>\n

      \n
    • Radio and TV transmitters.<\/li>\n
    • Radio and TV receivers.<\/li>\n<\/ul>\n

      \"2nd<\/p>\n

      Question 10.
      \nMention any two applications of Colpitts oscillator.
      \nAnswer:
      \nCollpitts oscillator is used in:<\/p>\n

        \n
      1. Radio and TV transmitters<\/li>\n
      2. Radio and TV receivers.<\/li>\n<\/ol>\n

        Question 11.
        \nMention any two advantages of a crystal oscillator over LC and RC oscillators.
        \nAnswer:<\/p>\n

          \n
        • They have high frequency stability.<\/li>\n
        • They are used as a reference for measurement and comparison of frequencies.<\/li>\n<\/ul>\n

          Question 12.
          \nMention the limitations of LC oscillators.
          \nAnswer:
          \nThe value of resistors and inductors change due to changes in temperture. Hence, the
          \nfrequency of LC and RC oscillator do not remain constant.<\/p>\n

          Question 13.
          \nWrite any two advantage of RC oscillators over LC oscillators.
          \nAnswer:<\/p>\n

            \n
          • RC oscillators provide constant output and good stability.<\/li>\n
          • RC oscillators do not require any inductor and hence size and cost get reduced.<\/li>\n<\/ul>\n

            Question 14.
            \nMention any two applications of a crystal oscillator.
            \nAnswer:
            \nCrystal oscillators are used in communication transmitters and receivers, in digital watches and calculators.<\/p>\n

            \"2nd<\/p>\n

            Question 15.
            \nDraw block diagram of 555 timer.
            \nAnswer:
            \n\"2nd<\/p>\n

            Question 16.
            \nDraw the diagram of bistable multivibrator.
            \nAnswer:
            \n\"2nd<\/p>\n

            2nd PUC Electronics Oscillators Three Marks Questions and Answers<\/h3>\n

            Question 1.
            \nExplain briefly how oscillations are produced in a tank circuit.
            \nAnswer:
            \nTank circuit or oscillatory circuit is a circuit which produces electrical oscillations of any desired frequency. A simple oscillatory circuit has a capacitor C and inductance L in parallel.
            \n\"2nd<\/p>\n

            When P is connected to A the capacitor gets charged to a potential V of the battery, with upper Plate being positive and lower plate negative.When p is conncted to B, the capacitor starts discharging through inductor L. when capacitor is fully discharged, the energy of magnetic field in the coil will be maximum.<\/p>\n

            Once capacitor is discharged, the magnetic field will begin to collapse and produce a counter emf. This keeps the current to flow in the opposite direction and the capacitor now gets charged with opposite polarity, making upper plate of capacitor negative and lower plate positive.
            \n\"2nd<\/p>\n

            After the collapsing magnetic field has recharged the capacitor, the capacitor now begins to discharge hence current now flows in the opposite direction. The interchange of energy between L and C is repeated again in the production of oscillations.<\/p>\n

            The frequency of oscillations generated by the LC tank circuit depends on values of L and C, given by\u00a0 \\(\\mathrm{f}=\\frac{1}{2 \\pi \\sqrt{\\mathrm{LC}}}\\)<\/p>\n

            \"2nd<\/p>\n

            Question 2.
            \nWith a circuit diagram, explain the principle of phase shift in the RC circuit.
            \nAnswer:
            \n\"2nd
            \nEach RC circuit is adjusted for 60\u00b0 phase shift. Hence the total phase shift from feedback network is 180\u00b0. The additional 180\u00b0 phase shift is introduced by op-amp inverting amplifier. As a result, phase shift around the loop will be 360\u00b0, satisfying the required condition for the positive feedback and the circuit acts as an oscillator.<\/p>\n

            Question 3.
            \nWith the circuit diagram, explain the principle of lead-lag network.
            \nAnswer:
            \n\"2nd
            \nA circuit in which output voltage leads or lags the input voltage is called a lead lag network. It has series combination of R1<\/sub> and C1<\/sub> and a paralel combination of R2<\/sub> and C2<\/sub>. At low frequencies, series capacitor C1 <\/sub>looks open and there is no output. At high frequencies, C2<\/sub> acts as short and no output is obtained. At some frequency f output is maximum if R1<\/sub>= R2<\/sub> = R and C1<\/sub>= C2<\/sub> =C, then frequency \\(\\mathrm{f}=\\frac{1}{2 \\pi \\mathrm{RC}}\\)<\/p>\n

            At low frequencies, phase angle is positive and the circuit acts as a lead network. At high frequencies, phase angle is negative and circuit acts as a lag network.\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 ‘<\/p>\n

            Question 4.
            \nDraw the circuit diagram of a Hartley oscillator. Mention the expression for the frequency of oscillations.
            \nAnswer:
            \n\"2nd
            \nFrequency \\({ f }=\\frac { 1 }{ 2\\pi \\sqrt { { LC } } } { Where }{ C }=\\frac { { C }_{ 1 }{ C }_{ 3 } }{ { C }_{ 1 }+{ C }_{ 2 } } \\)<\/p>\n

            Question 5.
            \nDraw the circuit diagram of Colpitts oscillator. Mention the expression for its feedback factor.
            \nAnswer:
            \n\"2nd<\/p>\n

            Question 6.
            \nDraw the circuit diagram of RC phase shift oscillator. Draw its output waveform.
            \nAnswer:
            \n\"2nd<\/p>\n

            \"2nd<\/p>\n

            Question 7.
            \nDraw the circuit diagram of wein bridge oscillator. Mention the expression for its voltage gain.
            \nAnswer:
            \n\"2nd<\/p>\n

            Question 8.
            \nDraw the circuit diagram of crystal oscillator. Draw the electrical equivalent circuit of a crystal.
            \nAnswer:
            \n\"2nd<\/p>\n

            2nd PUC Electronics Oscillators Five Marks Questions and Answers<\/h3>\n

            Question 1.
            \nWith a circuit diagram, explain the working of Hartley oscillator. Write the expression for its frequency and feedback factor.
            \nAnswer:
            \n\"2nd
            \nResistors R1<\/sub>R2<\/sub> and RE<\/sub> provide the required DC bias to the transistor. CC is coupling capacitor and CE<\/sub> is a bypass capacitor. RFC is radio frequency choke which isolates power supply from the oscillations at the collector. Inductors L1<\/sub>, L2<\/sub> with capacitor C forms the tank circuit. Frequency of oscillations
            \n\\(f=\\frac{1}{2 \\pi \\sqrt{L C}}\\) <\/span>Where L = L1<\/sub><\/span> + L2<\/sub><\/span><\/p>\n

            When power supply is switched on, collector current increases and charge the capacitor. When the capacitor is fully charged, it discharges through L1<\/sub> and L2<\/sub> and oscillations will be set up. The voltage across L2<\/sub> is feedback to amplifier circuit and that across L1<\/sub> is taken as output. 180\u00b0 phase shift is provided by the transistor amplifier and another 180\u00b0 phase shift is provided by the tank circuit. Thus totally 360\u00b0 phase shift is obtained, which is the required condition for \u2018 the sustained oscillations.
            \nThe voltage feedback ratio\u00a0 \\(\\beta=\\frac{\\mathrm{L}_{2}}{\\mathrm{L}_{1}}\\)<\/span><\/p>\n

            \"2nd<\/p>\n

            Question 2.
            \nDraw the circuit diagram of colpitts oscillator and explain its action. Write the expression for its frequency and feedback factor.
            \nAnswer:
            \n\"2nd
            \nThe resistors R1 <\/sub>R2<\/sub> and RE provide necessary DC bias to the transistor. CC is the coupling capacitor and CE is a bypass capacitor, RFC is radio frequency choke which prevents high frequency oscillations reaching the DC power supply. The tank circuit has an inductor and two capacitor C1<\/sub> and C2<\/sub> in series.<\/p>\n

            When power supply is switched on, the increasing collector current charges C1<\/sub> and C2<\/sub>. The potential across the two capacitors are in opposite phase. When the capacitors are fully charged, voltage across C2<\/sub> is fed back to amplifer circuit. The amplifier produces a phase shift of 180\u00b0 and the tank circuit produces a phase difference of 180\u00b0. Hence the total phase shift is 360\u00b0, which is the condition required for the sustained oscillations.<\/p>\n

            The feedback fraction is \\(\\beta=\\frac{C_{1}}{C_{2}}\\), and the frequency of oscillations produced is
            \n\"2nd
            \nQuestion 3.
            \nWith a circuit diagram, explain the action of a RC phase shift oscillator. Write the expression for its frequency and feedback factor.
            \nAnswer:
            \n\"2nd<\/p>\n

            It has op-amp as the amplifying stage and three RC cascaded RC network as the feedback circuit. The op-amp is used as an amplifier. The feedback circuit provides feedback voltage from the output back to the input of the amplifier. The op-amp is used in the inverting mode. Thus, op-amp gives a phase shift of 180\u00b0 at the output. An additional 180\u00b0 phase shift required for oscillations is provided by the 3 RC networks.<\/p>\n

            When the power supply is switched on, the noise voltage induced between the pin numbers 2 and 3 is amplified by the op-amp producing a phase shift of 180\u00b0. The output is fed to RC phase shift network which introduces a total phase shift of 180\u00b0 by charging and discharging action of a capacitor through the resitors. Each RC network produces a phase shift 60\u00b0 and hence three RC
            \n\\(f=\\frac{1}{2 \\pi R C \\sqrt{6}}=\\frac{0.065}{R C}\\)
            \nThe feedback fraction is \u03b2 = \\(\\beta =\\frac { R_{ i } }{ R_{ f } } =\\frac { 1 }{ 29 } \\)<\/p>\n

            \"2nd<\/p>\n

            Question 4.
            \nDraw the circuit diagram of Wein bridge oscillator and explain its working. Write the expression for the frequency and feedback factor.
            \nAnswer:
            \n\"2nd
            \nThe circuit diagram shows wein bridge oscillator in which wein bridge is connected between amplifier input terminal and the output terminal. The bridge has a series RjC, network in one arm and a parallel R2<\/sub>C, network in the adjoining arm. In the remaining arm of the bridge, resistors R3<\/sub>, R4<\/sub> are connected. The phase angle criterion for oscillation is that total phase shift around the circuit should be 0\u00b0.<\/p>\n

            This is possible only when output is fedback to the non\u00adinverting input without any phase shift since the lead-lag network does not produce any phase shift. This condition occurs only when the bridge is balance i.e., at resonance. The frequency of oscillation is given by \\(f=\\frac{1}{2 \\pi R C}=\\frac{0.159}{R C}\\)
            \nThe feedback fraction, \u03b2 = \\(\\frac{1}{3}\\)<\/p>\n

            Question 5.
            \nWith a circuit diagram, explain the working of crystal oscillator. Write the expression for
            \nits frequency of oscillation.
            \nAnswer:
            \n\"2nd
            \nCrystal oscillator works on the principle of piezo electric effect. According to piezo electric effect, when AC voltage is applied across the crystal, it vibrates at the frequency of the applied voltage. If the mechanical force is applied to make the crystal vibrate, then an AC voltage is generated across it. Quaertz, Rochelle salt and Tourmaline show this phenomena of piezo electric effect.<\/p>\n

            The resistors R1<\/sub>, and R2<\/sub>, and RE<\/sub> form voltage divider stabilised dc bias circuit. The radio frequency choke prevents oscillations produced from entering the dc power supply.<\/p>\n

            When the circuit is switched on, the noise signal generated increases the collector current which charges the capacitors C1<\/sub>, and C2<\/sub>. The discharging current induces an emf across plates of the crystal which oscillates and produces the resonant frequency. The crystal, C1<\/sub>, and C2 <\/sub>produce a phase shift of 180\u00b0 and the transistor produces a phase shift of 180\u00b0. Thus the phase shift around the loop is 360\u00b0, the require condition for the sustained oscillations.<\/p>\n

            The frequency of oscillations produced is
            \n\"2nd
            \nThe frequency stability of the crystal oscillator is very high because frequency of oscillation is unaffected by changes in supply voltage and transistor parameters.<\/p>\n

            \"2nd<\/p>\n

            Question 6.
            \nExplain briefly each part of block diagram of 555 timer
            \nAnswer:
            \n\"2nd
            \nIt has two comparators, an RS flip flop, npn transistor and three 5K\u03a9 resistors. Resistive network has three equal resistors and acts as a voltage divider.<\/p>\n

            When the threeshold voltage is greater than the control voltage, the comparator will set the flip flop and its output is HIGH. HIGH output from the flip flop saturates the discharge transistor T. The complementary output of the flip flop going to pin 3 is low. The condition will remain until comparator 2 triggers the flip flop even if the voltage at the threshold input falls below \\(\\frac{2}{3}Vcc\\) ie, comparator 1 can not couse flip flop to change again comparator 1 can only force the 3 flip flops output HIGH.<\/p>\n

            To change output of the flip flop to low’ state, the voltage at the input should fall below \\(\\frac{1}{3}Vcc\\)<\/p>\n

            The comparator 2 triggers flip flop output to low state. The output from flip flop turns the discharge transistor T2<\/sub> off. The output at pin 3 is high.<\/p>\n

            Problems with Solutions<\/span><\/p>\n

            Question 1.
            \nA transistor Colpitts oscillator has L= 4mH, C1<\/sub> =10nF, C2<\/sub>=10nF. Determine the frequency of oscillation.
            \nAnswer:
            \n\"2nd<\/p>\n

            Question 2.
            \nA Colpitts oscillator circuit is to generate a frequency of 24 kHz. The capacitors used are Cf<\/sub>= 0.2 \u03bcF, C2<\/sub>=0.22\u03bcF. Find the value of inductor used.
            \nAnswer:
            \n\"2nd<\/p>\n

            \"2nd<\/p>\n

            Question 3.
            \nA colpitts oscillator oscillates at 1.13MHz. If the inductor in the feedback network has a value of 20pH. and one of the capacitors value is 0.1 \u03bcF, calculate the value of the other capacitor.
            \nAnswer:
            \n\"2nd
            \n\"2nd<\/p>\n

            Question 4.
            \nCalculate the frequency and feedback ratio of the circuit given below.
            \nAnswer:
            \n\"2nd
            \n\"2nd<\/p>\n

            Question 5.
            \nA Hartley oscillator has L1<\/sub>=3mH, L2<\/sub>=5mH and C=10nF. Determine the frequency of oscillations.
            \nAnswer:
            \nL=L1<\/sub>+ L2<\/sub> = 3 + 5 = 8mH
            \nC = 10 \u03b7f = 10 x 10-9 <\/sup>F
            \n\"2nd<\/p>\n

            \"2nd<\/p>\n

            Question 6.
            \nA Hartley oscillator circuit is to generate a frequency of 1200 kHz. If the capacitor in the feedback network has a value of 220 pF and one of the inductor’s value is 20pH, calculate the other inductor.
            \nAnswer:
            \n\"2nd<\/p>\n

            Question 7.
            \nHartley oscillator oscillates at 54 kHz. The inductors used have inductances L1 <\/sub>= 30mH and L2<\/sub>= 60mH. Find the value of capacitance of the capacitor
            \nAnswer:
            \nf = 54 kHz
            \n= 54 x 103<\/sup> Hz
            \nL1<\/sub>= 30mH = 30 x 10-3<\/sup>H
            \nL2<\/sub>= 6omH = 60 x 10-3 <\/sup>H
            \nL = L1<\/sub> + L2<\/sub> = 30 + 60 = 90mH = 90 x 10-3<\/sup>H
            \n\"2nd<\/p>\n

            Question 8.
            \nCalculate the frequency and feedback ratio of the circuit given below.
            \nAnswer:
            \n\"2nd
            \n\"2nd
            \n\"2nd<\/p>\n

            \"2nd<\/p>\n

            Question 9.
            \nRC Phase shift oscillator uses three identical RC sections in the feedback network. The values of the components are R=680\u03a9 and C=220nF. Determine the frequency of oscillation.
            \nAnswer:
            \n\"2nd<\/p>\n

            Question 10.
            \nWhat should be the value of capacitor required for a phase shift oscillator to produce a frequency of 338 Hz, if the resistance used is 220\u03a9.
            \nAnswer:
            \n\"2nd<\/p>\n

            Question 11.
            \nThe frequency of phase shift oscillator is 125 Hz. If the value of the capacitance of the capacitor used is 0.22pF, calulate the value of resistance used.
            \nAnswer:
            \nf = 125Hz
            \nC = 0.22\u03bcf
            \n\"2nd<\/p>\n

            Question 12.
            \nThe frequency of Wein bridge oscillator is 1200 Hz. If the resistance value used is 820Q calculate the value of the capacitance used.
            \nAnswer:
            \n\"2nd<\/p>\n

            Question 13.
            \nThe RC network of Wein bridge oscillator consists of resistors and capacitors of values R1<\/sub>=R2<\/sub>=R=270 k\u03a9 and C1<\/sub>=C2<\/sub>=C=470\u03bcF. Determine the frequency of oscillation.
            \nAnswer:
            \n\"2nd<\/p>\n

            Question 14.
            \nThe frequency of Wein bridge oscillator is If the capacitance value used is
            \nC1<\/sub> =C2 <\/sub>C= 0.1\u03bcF, calculate the value of resistance R1<\/sub>=R2<\/sub>=R to be used.
            \nAnswer:
            \n\"2nd<\/p>\n","protected":false},"excerpt":{"rendered":"

            Students can Download 2nd PUC Electronics Chapter 6 Oscillators Questions and Answers, Notes Pdf, 2nd PUC Electronics Question Bank with Answers\u00a0helps you to revise the complete Karnataka State Board Syllabus and score more marks in your examinations. Karnataka 2nd PUC Electronics Question Bank Chapter 6 Oscillators 2nd PUC Electronics Oscillators One Mark Questions and Answers …<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[82],"tags":[],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/posts\/24157"}],"collection":[{"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/comments?post=24157"}],"version-history":[{"count":0,"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/posts\/24157\/revisions"}],"wp:attachment":[{"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/media?parent=24157"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/categories?post=24157"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/tags?post=24157"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}