List of top Electronics and Communication Engineering Questions

The orthogonal signals S1 and S2 satisfy the following relation.
In a PCM system, speech signal bandlimited to 4 kHz is sampled at 1.5 times Nyquist rate and quantized using 256 levels. The bit rate required to transmit the signal will be
An AM modulator develops an unmodulated power output of 400W across a 50\(\Omega\) resistive load. The carrier is modulated by a single tone with a modulation index of 0.6. If this AM signal is transmitted, the power developed across the load is
Which of the following Light source is popularly used in optical communication?
The Numerical aperture of a fiber describes the __________ characteristics.
NRZ and QPSK are respectively
The modulation index of amplitude modulation system is limited to unity because
Let an error control system uses (16, 3) block codes. The coding efficiency of the system will be
A direct sequence spread spectrum technique uses 10 flip-flop linear feedback shift register as PN code generator. The jamming margin produced by the system will be
In the absence of attenuation on the line \( (\alpha = 0) \), the Voltage Standing Wave Ratio (VSWR) is
What is the nature of radiation pattern of an isotropic antenna?
When an arbitrary length of any general transmission line, is terminated in an open circuit or a short circuit, its input impedance is determined completely by
The far field of an antenna varies with distance r as
A mode is a combination of a voltage V and current I, which propagate along z according to the common propagation factor of
The instruction XLAT in 8086 microprocessor is used to
For the given 8086 microprocessor instructions below, which is an invalid instruction?
On a radio frequency transmission line, the velocity of signals at a frequency of 125 MHz is \( 2.1 \times 10^8 \) m/sec. What is the wavelength of the signal on the line?
Moist soil has a conductivity of $\sigma = 10^{-3}$ S/m and $\epsilon_r = 2.5$. Find conduction current $J_c$. Given, $E = 6 \times 10^{-6} \sin 9 \times 10^{3} t$ V/m.
A wave is incident at an angle of 30°, from air to Teflon. Find the angle of transmission. Given, \(\epsilon_r\) = 2.1, \(\mu_1 = \mu_2\)
Calculate the value of LSB and MSB of a 12-bit DAC for 10V.
In 8085 microprocessor, unfortunately, two address lines namely A13 and A6 have become faulty and are stuck at logic 0. Which of the following address locations cannot be accessed in the memory?
Which characteristic of PLL is defined as the range of frequencies over which PLL can acquire lock with the input signal?
The output voltage of phase detector is
Which of these error-detecting codes enables to find double errors in Digital Electronic devices?
In order to check the CLR function of a counter