# Practice Quiz in Digital and Data Communication Networks Part 5

Online Practice Quiz in Digital and Data Communication Networks part 5 as one of the Communications Engineering topic.

This is the Online Practice Quiz in Digital and Data Communication Networks Part 5 as one of the Communications Engineering topic. In Preparation for the ECE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Examination Questions in Electronic System and Technologies, Communications Books, Journals and other Communications References.

### Continue Part V of the Online Practice Quiz

#### Quiz in Digital and Data Communication Networks

Question 41. What is the object of trellis coding?

A. To narrow bandwidth

B. To simplify encoding

C. To increase data rate

D. To reduce the error rate

Question 42. RZ encoding involves _______ levels of signal amplitude.

A. 1

B. 3

C. 4

D. 5

Question 43. The EIA-RS-232 standard defines _________ characteristics of the DTE-DCE interface.

A. Mechanical

B. Electrical

C. Function

D. ALL of these

Question 44. If the frequency spectrum of a signal has a bandwidth of 500 Hz with the highest frequency at 600 Hz, what should be the sampling rate according to the Nyquist theorem?

A. 200 samples/sec

B. 500 samples/sec

C. 1000 samples/sec

D. 1200 samples/sec

Question 45. If you have two close, compatible DTEs that can communicate data that do not need to be modulated. A good interface would be ________.

A. A null modem

B. An EIA-RS-232 modem

C. A DB-45 connector

D. A transceiver

Question 46. The encoding method specified in the EIA-232 standard is _________.

A. NRZ-I

B. NRZ-L

C. Manchester

D. Differential Manchester

Question 47. In _________ transmission, bits are transmitted simultaneously, each across its own channel.

A. Asynchronous serial

B. Synchronous serial

C. Parallel

D. A and B

Question 48. A cable range of 40 to _____ feet is possible according to the EIA-RS-449 standard.

A. 50

B. 400

C. 500

D. 4000

Question 49. Which of the following is most affected by noise?

A. PSK

C. FSK

D. QAM

Question 50. For a binary phase shift keying (BPSK) modulation with a carrier frequency of 80 MHz and an input bit rate of 10 Mbps. Determine the minimum Nyquist bandwidth.

A. 40 MHz

B. 10 MHz

C. 20 MHz

D. 50 MHz