Chapter 14, Feedback and Oscillator Circuits Video Solutions, Electronic Devices and Circuit Theory

01:18

Problem 1

Calculate the gain of a negative-feedback amplifier having $A=-2000$ and $\beta=-1 / 10$.

Varsha Aggarwal

Numerade Educator

01:01

Problem 2

If the gain of an amplifier changes from a value of $-1000$ by $10 \%$, calculate the gain change if the amplifier is used in a feedback circuit having $\beta=-1 / 20$.

Narayan Hari

Numerade Educator

01:11

Problem 3

Calculate the gain, input, and output impedances of a voltage-series feedback amplifier having $A=-300, R_{i}=1.5 \mathrm{k} \Omega, R_{o}=50 \mathrm{k} \Omega$, and $\beta=-1 / 15$

Brian Francisco

Numerade Educator

01:41

Calculate the gain with and without feedback for an FET amplifier as in Fig. 7 for circuit values $R_{1}=800 \mathrm{k} \Omega, R_{2}=200 \Omega, R_{o}=40 \mathrm{k} \Omega, R_{D}=8 \mathrm{k} \Omega$, and $g_{m}=5000 \mu \mathrm{S}$.

Kajal Gautam

Numerade Educator

03:10

Problem 5

For a circuit as in Fig. 11 and the following circuit values, calculate the circuit gain and the input and output impedances with and without feedback: $R_{B}=600 \mathrm{k} \Omega, R_{E}=1.2 \mathrm{k} \Omega, R_{C}=$ $4.7 \mathrm{k} \Omega$, and $\beta=75$. Use $V_{C C}=16 \mathrm{~V}$.

James Kiss

Numerade Educator

02:55

Problem 6

An FET phase-shift oscillator having $g_{m}=6000 \mu \mathrm{S}, r_{d}=36 \mathrm{k} \Omega$, and feedback resistor $R=12 \mathrm{k} \Omega$ is to operate at $2.5 \mathrm{kHz}$. Select $C$ for specified oscillator operation.

Aja S

Numerade Educator

08:15

Problem 7

Calculate the operating frequency of a BJT phase-shift oscillator as in Fig. $21 \mathrm{~b}$ for $R=6 \mathrm{k} \Omega, C=1500 \mathrm{pF}$, and $R_{C}=18 \mathrm{k} \Omega$

Ramesh Singh

Numerade Educator

01:24

Problem 8

Calculate the frequency of a Wien bridge oscillator circuit (as in Fig. 23) when $R=10 \mathrm{k} \Omega$ and $C=2400 \mathrm{pF}$.

Km Neeraj

Numerade Educator

03:01

Problem 9

For an FET Colpitts oscillator as in Fig. 26 and the following circuit values determine the circuit oscillation frequency: $C_{1}=750 \mathrm{pF}, C_{2}=2500 \mathrm{pF}$, and $L=40 \mu \mathrm{H}$.

Averell Hause

Carnegie Mellon University

05:14

Problem 10

For the transistor Colpitts oscillator of Fig. 27 and the following circuit values, calculate the oscillation frequency: $L=100 \mu \mathrm{H}, L_{R F C}=0.5 \mathrm{mH}, C_{1}=0.005 \mu \mathrm{F}, C_{2}=0.01 \mu \mathrm{F}$, and
$C_{C}=10 \mu \mathrm{F}$.

Donald Albin

Numerade Educator

01:25

Problem 11

Calculate the oscillator frequency for an FET Hartley oscillator as in Fig. 29 for the following circuit values: $C=250 \mathrm{pF}, L_{1}=1.5 \mathrm{mH}, L_{2}=1.5 \mathrm{mH}$, and $M=0.5 \mathrm{mH}$.

Varsha Aggarwal

Numerade Educator

01:07

Problem 12

Calculate the oscillation frequency for the transistor Hartley circuit of Fig. 30 and the following circuit values: $L_{R F C}=0.5 \mathrm{mH}, L_{1}=750 \mu \mathrm{H}, L_{2}=750 \mu \mathrm{H}, M=150 \mu \mathrm{H}$, and
$C=150 \mathrm{pF}$.

Narayan Hari

Numerade Educator

03:48