Analog Communications Questions and Answers – Pre Emphasis and De Emphasis

«
»

This set of Analog Communications Multiple Choice Questions & Answers (MCQs) focuses on “Pre Emphasis and De Emphasis”.

1. Super heterodyne receivers needs an extra circuitry for frequency conversion.
a) True
b) False
View Answer

Answer: a
Explanation: Super heterodyne receiver mixes the incoming signal frequency with the locally generated signal frequency, using a mixer, in order to convert the incoming RF signal to a low frequency signal which can be processed easily. It has better sensitivity and selectivity but it needs an extra circuitry for frequency conversion.

2. Neper is ________ decibel.
a) smaller than
b) larger than
c) equal to
d) exactly twice of
View Answer

Answer: b
Explanation: Neper is a unit used to express ratios, such as gain, loss and relative values. One neper is equal to 8.685 dB. Hence it is greater than dB.

3. The coupling used in stoneman transmission bridge is ________
a) Inductive
b) Resistive
c) Capacitive
d) Combination of inductive and capacitive
View Answer

Answer: c
Explanation: Stoneman transmission bridge is used in telephone communication to separate voice path from signal path and battery. Capacitive coupling is used in it.
Note: Join free Sanfoundry classes at Telegram or Youtube
advertisement
advertisement

4. Which statement is true about Square Law modulators?
a) it is used for frequency modulation
b) it is used for pulse width modulation
c) it is used for amplitude modulation
d) it is used for phase modulation
View Answer

Answer: c
Explanation: In amplitude modulation, the amplitude of the carrier wave is varied with respect to the instantaneous amplitude of the wave to be transmitted. Square Law modulators are generally used for generation of amplitude modulation. They have nonlinear current-voltage characteristics. They are highly nonlinear in low voltage region.

5. Which statement is true about ring modulator?
a) it is used for DSB-SC generation
b) it is used for SSB-SC generation
c) it is a summation modulator
d) it is used for AM generation
View Answer

Answer: a
Explanation: Ring Modulator is used for generating DSB-SC waves. It is a product modulator having four diodes connected in the form of a ring, which suppresses the carrier and allows only the two sidebands to be passed.

6. In ergodic process, ensemble and time averages are identical.
a) False
b) True
View Answer

Answer: b
Explanation: In ergodic process, ensemble and time averages are identical to each other.

7. What is the amount of information in continuous signal?
a) zero
b) infinite
c) 2 bits
d) 4 bits
View Answer

Answer: b
Explanation: In any continuous signal, the amount of information that comes out is always infinite.
advertisement

8. Audio frequency range lies between _________
a) 2 MHz to 20 MHz
b) 20 Hz to 20 KHz
c) 20 KHz to 200 KHz
d) 20 MHz to 200 MHz
View Answer

Answer: b
Explanation: As per standards audio frequency range lies in between 20 Hz to 20 KHz. This is the human audible range.

Sanfoundry Global Education & Learning Series – Analog Communications.

advertisement

To practice all areas of Analog Communications, here is complete set of 1000+ Multiple Choice Questions and Answers.

advertisement
advertisement
Subscribe to our Newsletters (Subject-wise). Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

Subscribe to his free Masterclasses at Youtube & technical discussions at Telegram SanfoundryClasses.