Electronic systems

Question 1

What is a system?

Answer 1

A system is a group of interrelated parts that perform a
specific function

Question 2

What is an input?

Answer 2

An input is the voltage, current or power that is applied
to an electrical circuit to achieve a desired result

Question 3

What is an output?

Answer 3

The result obtained from the system after
processing its input(s)

Question 4

What is an electrical system?

Answer 4

An electrical system deals with electric power

Question 5

What is an electronic system?

Answer 5

An electronic system deals with signals; changing electrical or electromagnetic quantities that carry information

Question 6

What is an electrical circuit?

Answer 6

An electrical circuit must form a complete path from a
power or signal source to a load, and back to the source

Question 7

What is a block diagram?

Answer 7

A block diagram (flowchart) is a model of a system that represents its structure in a graphical format using labelled blocks to represent functions and lines to represent the signal flow

Question 8

What are analog quantities?

Answer 8

• Quantities that have continuous values over a limit range such as time.
• Most natural quantities that we see are analogue and vary continuously.

Question 9

What can digital systems do?

Answer 9

Digital systems can process, store, and transmit data more efficiently but can only assign discrete values to each point

Question 10

What are analog signals?

Answer 10

A waveform that continually varies in a certain manner

Question 11

Give examples of analog signals

Answer 11

• Sine waves
• Sound waves
• Amplitude modulated (AM) signals
• Frequency modulated (FM) signals

Question 12

What are digital signals?

Answer 12

A waveform that represents a sequence of discrete
values (1’s and 0’s)

Question 13

What is digital modulation?

Answer 13

• Digital modulation provides a means of transmitting
  data from one system to another (such as a form of wave).
• It affects the bandwidth of the transmitted signal

Question 14

What does Pulse-code Modulation (PCM) do?

Answer 14

• PCM uses a sequence of digital codes (binary values) to represent a sampled analog signal
• The higher the sampling rate, the more accurate the digitized waveform

Question 15

What are the two circuit states that digital electronics uses?

Answer 15

• They are represented by two different voltage levels called HIGH and LOW
• The voltages represent numbers in the binary system

Question 16

What is a single number called in binary and value can it have?

Answer 16

• A bit
• A bit can have the value of either a 0 or a 1, depending on if the voltage is HIGH or LOW

Question 17

What do digital waveforms do and what are they?

Answer 17

• Digital waveforms change between the LOW and HIGH levels
• A Digital Waveform Carries Binary Information

Question 18

What is a positive-going pulse?

Answer 18

One that goes from a normally LOW level to a HIGH level and then back again

Question 19

What is a negative-going pulse?

Answer 19

One that goes from a normally HIGH level to LOW level and then back again

Question 20

What is a pulse?

Answer 20

A sudden change from one level to another, followed after a time, called the pulse width, by a sudden change back to the original level

Question 21

What are periodic and Nonperiodic pulse waveforms?

Answer 21

• Periodic are composed of pulses that repeats in a fixed interval called the period
• Nonperiodic has no pattern

Question 22

What does a timing diagram show?

Answer 22

A timing diagram is used to show the relationship
between two or more digital waveforms

Question 23

How can data be transmitted and which one is faster?

Answer 23

• Data can be transmitted by either serial transfer or
  parallel transfer
• Serial transmission is faster as you only have one line to stabilise