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What is D-FF?a.It is called the D flip-flop for this reason, since the output takes the valueof the D input or Data input, and Delays it by one clock cycle.

What is the basic difference between Latches and Flip flops?a.latch-clocks are not required,asynchronous,switch. flip flop - clock is required,synchronous,storing element.

What is a multiplexer?a. A device that combines several input signals into a single output signal

How can you convert an SR Flip-flop to a JK Flip-flop?a.

How can you convert an JK Flip-flop to a D Flip-flop?a.

What is Race-around problem? How can you rectify it?a.in flip flop race around problem will accur when both

the inputs are high. it can be prevented by usingmaster slave jk flip flop

Which semiconductor device is used as a voltage regulator and why?a.A silicon semiconductor device used as a voltage regulator because of its ability to maintain an almost constant voltage with a wide range of currents.

Explain an ideal voltage source?a. an ideal voltage source is a circuit element where the voltage across it is independent of the current through it.

Explain zener breakdown and avalanche breakdown?a.When a high reverse voltage is applied to the highly doped p-n junction then a

t a particular voltage breakdown isoccured because of increase in the value of barrier potential and it increases at such a level that at aparticular voltage the electrons in the atom get ionised and thus results in the increase in the no of electronswhich results in the rapid increase in the value of current and this increase incurrent known as zener breakdown voltage.

avalanche breakdown occurs when a high reverse voltage is applied to the normalp-n junction thendue to high voltage the electrons get ejected from the stationary atoms which results in rapid increase in the

value of current and is known as avalanche breakdown.

What are the different types of filters?What is the need of filtering ideal response of filters and actual response of filters?What is sampling theorem?What is impulse response?Explain the advantages and disadvantages of FIR filters compared to IIR counterparts.What is CMRR?Explain half-duplex and full-duplex communication?Which range of signals is used for terrestrial transmission?Why is there need for modulation?

Which type of modulation is used in TV transmission?Why we use vestigial side band (VSB-C3F) transmission for picture?When transmitting digital signals is it necessary to transmit some harmonics in

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addition to fundamental frequency?For asynchronous transmission, is it necessary to supply some synchronizing pulses additionally or to supply or to supply start and stop bit?BPFSK is more efficient than BFSK in presence of noise. Why?What is meant by pre-emphasis and de-emphasis?Explain 3 dB cutoff frequency? Why is it 3 dB, not 1 dB?Explain ASCII, EBCDIC?