In the circuit shown below, switch S1 and S2 are in open and close position respectively for long time. At $$t = t_o$$, switch S1 is closed and switch S2 is opened. What would be the current through R1 immediately after the transition of switches?
ISRO Scientist or Engineer Electronics 2014
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A digital board has a unipolar square clock of 250MHz. If the clock on the board at all places should have all the harmonic components which have more than 10% of DC value, the board has to be designed forat least
A switch is connected in between a 12V battery and an uncharged capacitor and a 1 KΩ resistor. At the time instant when the switch is closed, the voltage across the capacitor is:
Which type of timing violation will occur, If a digital IC is operated at clock frequency which is higher than its specified maximum clock frequency?
If the maximum effective aperture of a radiating small loop of constant current is $$\left(\frac{3}{32 \pi}\right) m^2$$, the wavelength of the radiated electromagnetic wave is:
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Match the following:
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Which of the following computation will take minimum number of clock cycles, if it is implemented on 8051 micro-controller? Following is variable declaration in c code:
unsigned int a, b;
Using a quarter wave transformer of characteristic impedance 1 Ω, a load impedance of 100 Ω will be transformed to an input impedance of value:
What is the output signal level of following circuit?
The effect of channel coding in communication channels is :
For a point charge having electric flux density, $$D = \frac{Q}{4 \pi r^2}a_r$$, where $$a_r$$ is the unit vector in radio direction; volume charge density $$\rho_v$$ is:
What is Discrete Time Fourier Transform (DTFT) of following signal?
$$x(n) = a^n$$ where $$n \geq 0, -1 < a < 1$$
In the near field, the radiated wavestake the form of :
The zener diode shown in following figure is temperature compensated and current gain $$\beta$$ of transistor is very high. If current through 100 ohm resistor is 55mA at $$25^\circ C$$, what is the approximate current throughit at $$65^\circ C$$?
Wewish to transmit a digital voice at 32 Kbps through a communication channel having bandwidth of 3000 Hz. The received signal to noise powerratio is 30 dB. State which of the following statementis true :
Consider a standard rectangular and a circular waveguide having same dominant mode cut-off frequency, determine the ratio of area of circular waveguide to rectangular waveguide:
What is the lowest level of abstraction in any hardware description language?
With the introduction of negative feedback, the gain-bandwidth product of an amplifier
For a BER of $$10^{-5}$$, which modulation schemewill require minimal power?
Which one of following is not synthesizable VHDL statement?
Subsystem A requires two voltages V1 and V2 with equal power ratings. Power conversion scheme adapted for the power supply design is shown in the following figure. Whatis the overall power conversion efficiency?
Which of the following modulation scheme is most bandwidth efficient?
A Colpitts Oscillator is having tank capacitances of InF and 10nF, and inductance of 0.1 $$\mu$$ H. The gain required by the circuit to start oscillating is :
A digital CMOS IC operating at 10MHz clock frequency consumes 100mW power; the same IC operating at 15 MHz clock frequency consumes 140mW power. Whatis the static power consumption of the IC?
An amplifier has a gain of 50 dB, and noise figure of 10dB. Assuming an ambient temperature of 300 K, what will be the total equivalent noise temperature at the input of the amplifier?
Diodes in the following circuit are ideal. Which is the correct waveform across $$R_L$$?
Identify the modulation schemes for the shown signal constellation diagrams
The Fourier Transform of a discrete and aperiodic signal is:
In the following circuit, Y can be expressed as:
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Which modulation scheme would you suggest for high speed data transmission over a fading channel?
For a two port network to be reciprocal, its Scattering parameters must satisfy the following condition, for i = 1, 2 ; j = 1, 2
In the following circuit, what sequence is followed by A and B on rising edge of CLK after reset is de-asserted?
In an axial mode operation of a helical antenna, maximum field radiated by the antenna is:
Which of the following theorem is applicable for both linear and non-linear circuits?
What is the maximum data rate that can be transmitted using a QPSK modulation with a roll-off factor of 0.2 for a 36 MHz transponder?
Consider a single stage tuned amplifier having 3dB bandwidth of 100KHz. Determine the bandwidth if two such single stage tuned amplifiers are cascaded:
500 Bytes of data needs to be transmitted from an UART every 100ms. What should be the minimum transmission baud rate of UART, assuming1 start bit, 8 data bits and 2 stop bits?
What is the value of the major cross-sectional dimension(width) of a rectangular waveguide with dominant TE19 mode propagation, if its cut off frequency is 10 GHz?
In a Traveling-wave Tube, the velocity of electron beam with respect to the axial velocity of RFfield is kept...
In satellite communication, scrambling is mainly used for -
Scattering Matrix for a microwave network, which is matchedatall the ports, will satisfy the following condition:
Following waveform shows output of a 4 bit DAC with 5V reference voltage. The 4 bit digital input of DAC is connected to 4 bit up counter, the one bit input of DAC Is stuck at ‘0’, which is this bit ?
Which of the followinghasthe highest skin depth?
A network contains linear resistors and ideal voltage sources. If values of all the resistors are doubled,then voltage across each resistor is
A coherent QPSK demodulatoris required on ground for receiving data from a LEO satellite. What should be optimum order of PLL in the carrier phase tracking loop?
VSWR of purely resistive load of normalized value n + j0 for n < 1 is :
Two discrete time systems have impulse response $$h_1[n] = \delta[n - 3]$$ and $$h_2[n] = \delta[n - 5]$$. If these two systems are cascaded, thenthe overall impulse response of the cascaded system is
Frequency range of Ka-band EM waves is
Following four resistances are connectedin parallel; the largest power is dissipated by ....
1) 2.4 Ω, 1W
2) 5.1 Ω, 2W
3) 10 Ω, 5W
4) 22 Ω, 10W
Eye diagram gives us an idea of -
Determine the correlation coefficient between the pulses x(t) and y(t) shown in the fig. below :
What is 4 point Discrete Fourier Transform of signal x(n) = (1, 2, 3, 4)
The valueof axialratio of a $$45^\circ$$ linearly polarized EM wavein dB is
If an input signal with non-zero dc component is applied to a low pass RC network with single resistor R and single capacitor C as shown below, the dc component in the output will be :
The thermal noise spectral density generated in a resistor kept at $$t^\circ C$$ is given by:
What are poles and zeros of a system having following transfer function?
$$H(z) = (1 - z^{-2})(1 + 1.3 z^{-1} + 0.36 z^{-2})$$
The change in phase of an electromagnetic wave normally incident on a perfect conducting wall is?
What is the turns ratio of the transformer needed to match a 1 kΩ source resistance to a 50 Ω load?
A satellite communication link has both uplink and downlink $$\frac{C}{N_o}$$, of 50dB-Hz. What would be overall link $$\frac{C}{N_o}$$?
Determine polarization loss factor for a circularly polarized signal upon reception by linearly polarized antenna
Which instruction of 8051 microcontroller is used for reading data from code memory?
If frequency is decreased 4 times, then skin depth of an Electromagnetic wave inside a conductor will be :
In the circuit shown below, the current through 10 Ω resistor is :
If two tones $$f_1$$ and $$f_2$$ are amplified by a non-linear amplifier, which frequency components would be present in output?
When a sinusoidal voltage wave drives a Schmitt Trigger, the output is a:
What will be content of Stack Pointer if following assembly code of 8051 microcontroller is executed immediately after reset?
PUSH 00h
POP OIh
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A resistor and a capacitor are connected in series with a sine wave generator having frequency suchthat the resistance and the capacitive reactance are same i.e. voltage across capacitance, $$V_c$$ is equal to Voltage across Resistance, $$V_R$$. If the frequency ofthe sine wave generator is doubled, then
In CMOS designs, why size of PMOS is kept larger than size of NMOS?
A plane wave with a frequency of 3 GHz is propagating in an unbounded medium with relative permittivity $$ε_r = 6$$ and permeability $$\mu_r = 1.5$$, the phase velocity for this wave in this medium is
Which of the following statements is NOT true:
The Boolean equation for Y in the following circuit is
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Which logical function is implemented by following Transmission Gate based circuit?
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Which of the following meters is based on the principle of Hall Effect?
