# Practice Quiz in Wire and Wireless Communications System Part 51

Online Practice Quiz in Wire and Wireless Communications System part 51 as one of the Communications Engineering topic.

This is the Online Practice Quiz in Wire and Wireless Communications System Part 51 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 LI of the Online Practice Quiz

#### Quiz in Wire and Wireless Communications System

Question 501. He designed and built the first transmitter and receiver for a telephone set.

A. Alexander Graham Bell

B. Alexander Bain

C. Antonio Meucci

D. Philipp Reis

Question 502. What tones carry map information using facsimile?

A. 1300 Hz and 2400 Hz

B. 2400 Hz and 2500 Hz

C. 1200 Hz and 2400 Hz

D. 1500 Hz and 2300 Hz

Question 503. A signalling technique wherein a number of voice paths is carried over one common channel instead of having individual voice channels.

A. In band signalling

B. Out of band signalling

C. Common channel signalling

D. Alternate channel signalling

Question 504. For crosstalk to be considered intelligible, at least ________ words are intelligible to the listener in a seven second period.

A. 5

B. 6

C. 4

D. 3

Question 505. What is used to transmit more than one conversation over a path?

A. Hybrid

B. Tandem

C. Multiplexing

D. All of these

Question 506. The signal heard on the telephone line that indicates readiness of the central office in receiving address or telephone number.

A. Dial tone

B. Ringing tone

C. Busy tone

D. Congestion tone

Question 507. dBa is a noise unit which uses a tone of 1000 Hz and a power level of

A. -85 dBm

B. -90 dBm

C. 85 dBm

D. -80 dBm

Question 508. By definition, speech power is equal to v.u. reading minus 1.4 dB plus log of N, where N is

A. The number of lines used

B. The number of transmitters used

C. The number of persons speaking

D. The number of listeners listening

Question 509. That part of the telephone network between the telephone instrument at the subscriber premises and the central office equipment is called the _______________.

A. Inter-office trunk

B. Tie line

C. Subscriber loop

D. Service drop wire

Question 510. A recorder helix in facsimile?

A. insulated drum with one turn wire

B. opaque drum with one turn scratch

C. clear sided with one turn wire

D. insulated drum with one turn scratch