The value of C which gives the critical damping in the given circuit is
ISRO Scientist or Engineer Electronics 2006
For the following questions answer them individually
A series RLC circuit resonates at 3 MHz and has 3-dB bandwidth of 10 kHz. The Q of the circuit at resonance
The value of resistance R shown in the given figure is
At 3-dB frequencies, current in the series RLC circuit equal current at resonance multiplied by
A series RLC circuit resonates at 1000 kHz. At frequency of 995 kHz, the circuit impedance is
If each stage had gain of 10dB and noise figure of 10dB, then the overall noise figure of two-stage cascade amplifier will be
In Sigma-delta ADC, high bit accuracy is achieved by
Let s(t) denote the delta function. The value of the integral
$$\int_{-a}^{a}\delta(t) \cos \left(\frac{3t}{2}\right)dt$$ is
Consider the compound system shown in the above figure. Its output is equal to the input with a delay of two units. If the transfer function of the first system is given by $$H_1(Z) = \frac{Z - 0.5}{Z - 0.8}$$, then the
The z-transform of the signal
$$x(n) = \begin{cases}1, & n = -1\\2, & n = 0 \\ -1, & n = 1 \\1, & n = 2 \\0, & otherwise \end{cases}$$
For the circuit shown in the given figure, the voltage $$V_{AB}$$ is
The equivalent Capacitance across 'ab' will be
The transfer function, $$T(s) = \frac{s}{s + a}$$ is that of a
A particular current is made up of two components: a 10 A dc and a sinusoidal current of peak value of 1.414 A. The average value of the resultant current is
By doubling the sampling frequency
The output voltage ($$v_o$$) of the circuit shown in the given figure is
Assuming that only the X and Y logic inputs are available and their complements $$\overline{X}$$ and $$\overline{Y}$$ are not available, what is the minimum number of two-input NAND gates requires to implement $$X \oplus Y$$
In the given network of AND and OR gates f can be written as:
A Pulse train with a frequency of 1MHz is counted using a modulo 1024 ripple-counter built with J-K flip-flops. For proper operation of the counter the maximum permissible propagation delay per flip-flop stage is
The A/D converter used in a digital voltmeter could be (1) successive approximation type (2) Flash converter type (3) Dual slope converter type. The correct sequence in the increasing order of their conversion times is
The resolution of a DIA converteris approximately 0.4% ofits full-scale range. It is
In a microprocessor, the resister which holds the address of the next instruction to be fetched is
In microcomputer, WAIT States are used to
Which of the following statements are correct
1. A flip-flop is used to Store 1 bit of information
2. Race-around condition occurs in a J-K flip-flop when both the inputs are 1
3. Master-slave configuration is used in flip-flops to store 2 bits of information
4. A transparent latch consists of a D-type flip-flop
How many 1 ‘s are present in the binary representation of
$$3 \times 512 + 7 \times 64 + 5 \times 8 + 3$$?
For emitter-coupled logic, the Switching speedis very high because
The out put of the circuit shown below is
Gray code for number 7 is
10 bit A/D converters, the quantization error is given by (in percent)
For the switch circuit, taking open as 0 and closed as 1, the expression for the circuit Y.
The Boolean expression for the shaded area in the Venn diagram is
If the memory chip size is 256*1 bits, then the number of chips required to make up 1K bytes of memory is
Given the decimal number — 19, an “eight bit two’s complement representation is given by
The function shown in the figure when simplified will yield a result with
The logic circuit given below converts a binary code $$Y_1Y_2Y_3$$ into
A 4-bit Synchronous counter uses flip-flops with Propagation delay time of 25 ns each. The maximum possible time required for change of state will be
An electromagnetic wave incident on a Perfect conductor is :
The characteristic impedance of a lossless transmission line is given by
A lossless line of 50 ohms is terminated in a load of 100 ohms resistive. The VSWR is
Which of the following does not exist in waveguides
Two carriers of 2 GHz and 4 GHz respectively are frequency modulate by a signal of 10KHz, such that bandwith of the FM signal in the two cases are same. The peak deviation in the two cases are in the ratio of
The bandwidth required for QPSK modulated channel is
Magic T is
Diplexer is made of
The gain G of an antenna of effective area A is given by
If the short circuit and open circuit impedance ofa line are 5 and 20Ω respectively the characteristic impedanceis given by
The input impedance of short circuited line of length l where $$\frac{\lambda}{4} < l < \frac{\lambda}{2}$$, is
Maximum coding gain in
Noise figure of an amplifier depends on
BCH code belongs to
When a carrier is phase modulated, with an integrated modulating signal, the resultant is
A satellite orbiting in 600 km orbit transmits 5 GHz frequency. The Doppler shift observed at the ground station, when the satellite is over head of the station is
A communication channel disturbed by additive white Gaussian noise has a bandwidth of 4kHz and SNR of 15. The highest transmission rate that such a channel can Support (in k-bits/sec) is
A dual directional coupler is connected in a microwave reflectometer measurement setup. The reading of the power meter in the forward direction is 100 mW and in the reverse direction 4 mw. The VSWR is
Linear amplifier with a gainof 30dB is fed with $$1.0 \mu W$$ power, the output power of the amplifier
10Watts RF Power is transmitted with a circular polarized antenna having gain of 4 0dB. A receiving antenna has vertical polarization The path loss is 100 dB. The receiving signal is
$$\overrightarrow{P} = 2i - 3j, \overrightarrow{Q} = -3i + 4j - 2k$$, and $$\overrightarrow{R}$$ are in equilibrium, if $$\overrightarrow{R}$$ is
Arigid bodyis rotating with constant angular velocity $$\omega$$ about a fixed axis, if $$\nu$$ is the velocity of a point of the body, then curl $$\nu =$$
Laplace transform of $$\sin^3 2t$$ is
The value of the determinant
Solution of $$(D^2 + 4)y = \sin^2 x$$, is
The value of k for which the lines $$2x + y - 1 = 0, 4x + 3y - 3 = 0$$ and $$3x + ky - 2 = 0$$, are concurrent is
A box contains 5 black and 5 red balls. Two balls are-randomly picked one after another from the box, without replacement. The probability for both balls being red is
$$x^3 + x \sin x$$ is
$$\int \frac{dx}{x \sqrt{x^2 - a^2}}$$ is
Eigen values of $$\begin{bmatrix}-5 & 2 \\2 & -2 \end{bmatrix}$$ are
The approximate equivalent resistance at the points $$X_1$$ and $$X_2$$ in the circuit shown below
An inductor supplied with 50 V ac with a frequency of 10 kHz passes a current of 7.96 mA. The value of inductor is
Ina capacitor, the electric charge is stored in
Oscillator requires
Which loss in a transformer varies significantly with load?
The resistance of a parallel circuit consisting of two resistors is 12 Ω One of the resistance wires breaks and the effective resistance becomes 18Ω. The resistance of the broken wire is
Time constant of a Series R-L circuit equals
A dc voltage V is applied at time t = 0 to a series RC circuit. The steady state current is
The given circuit represents a
The very low frequency gain of the low pass filter shown in the given figure is
The time-constant of the network Shown in the figure is
For the circuit shown below the current l flowing through the circuit will be
When L is doubled and is halved, the resonance frequency of series tuned circuit becomes
In a Series resonant circuit, with the increase in L
