Question 1

In which of the following is the sample signal voltage held constant between samples?

Accepted Answer

A)  natural sampling 
B)  sample and hold 
C)  flat-top sampling 
D)  none of the above

Question 2

The type of PCM coding scheme that is popular in optical systems, satellite telemetry links, and magnetic recording systems is:

Accepted Answer

A)  phase-encoded and delay modulation 
B)  RZ - return to zero 
C)  NRZ - non-return to zero 
D)  multilevel binary

Question 3

An early alphanumeric 5-bit code that was developed in the days of teletype machines that has limited power is known as:

Accepted Answer

A)  the Baudot code 
B)  EBCDIC 
C)  ASCII 
D)  the Gray code

Question 4

An alias signal is:

Accepted Answer

A)  a signal that has a frequency equal to the difference between the applied analog frequency and the sampling frequency. 
B)  usually filtered out by anti-aliasing filters in PCM systems 
C)  a signal that forms in a PCM system that has failed to meet the Nyquist sampling rate 
D)  all of the above

Question 5

The distance of a received code (00111) from a valid code of (00101);

Accepted Answer

A)  1 
B)  3 
C)  4 
D)  2

Question 6

Given a (7,4) cyclic code, the length of the message is

Accepted Answer