List of top Electronics and Communication Engineering Questions

The instruction XLAT in 8086 microprocessor is used to

For the given 8086 microprocessor instructions below, which is an invalid instruction?

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

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?

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

In the absence of attenuation on the line \( (\alpha = 0) \), the Voltage Standing Wave Ratio (VSWR) is

Which of the following statements is true about error detection techniques used on communications link?

Consider an air filled rectangular waveguide with a cross section of 5cm x 3cm. For this waveguide, the cut off frequency (in MHz) of \(TE_{21}\) mode is

The orthogonal signals S1 and S2 satisfy the following relation.

Which of the following Light source is popularly used in optical communication?

The Numerical aperture of a fiber describes the __________ characteristics.

When mean optical power launched into an 8 km length of fiber is 12 \(\mu\)W, the mean optical power at the fiber output is 3 \(\mu\)W. Find the overall signal attenuation in dB

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

The Modulating frequency in narrow band frequency modulation is increased from 10 kHz to 20 kHz. The bandwidth is

Transfer characteristics of JFET is drawn between

Forward current of 75mA passes through a diode for a forward drop of 0.6V. Find the forward resistance of the diode.

Early effect in bipolar transistor is caused by

Find the operating region of N-channel MOSFET with VGS = 1.4V, VTN = 0.5V, VDS = 1.8V

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.

Calculate the value of LSB and MSB of a 12-bit DAC for 10V.

If the data rate of delta modulator output is 43.2 kbps, for the input signal of 3.6 kHz, then the sampling rate used is equal to,

The shape of the rectangular window function is changed to other function such as Hamming and Blackman window functions so that

A wave is incident at an angle of 30°, from air to Teflon. Find the angle of transmission. Given, \(\epsilon_r\) = 2.1, \(\mu_1 = \mu_2\)