Chapter 2: Electronic Fundamentals for Communications

Question 1

______ means amplification. It is the ratio of a circuit’s output to its input.

Answer 1

Gain

Question 2

An amplifier is _____ when two or more stages are connected together.

Answer 2

Cascaded

Question 3

_____ refers to a loss introduced by a circuit or component. If the output signal is lower in amplitude than the input, the circuit has loss or attenuation.

Answer 3

Attenuation

Question 4

The ______ is a unit of measure used to express the gain or loss of a circuit.

Answer 4

Decibel

Question 5

The ____ is the number obtained when the base is raised to the logarithm which is the exponent.

Answer 5

Antilog

Question 6

When a _______ value is computed by comparing a power value to 1mW, the result is a value called the dBm.

Answer 6

Decibel

Question 7

The value ___ is a decibel gain attenuation figure where the reference is the carrier.

Answer 7

dBc

Question 8

Virtually all communications equipment contains _________ made up of inductors and capacitors that ___________at specific frequencies.

Answer 8

Tuned circuits
Resonate

Question 9

Opposition to alternating current flow offered by coils and capacitors is known as __________.

Answer 9

Reactance

Question 10

_______ is the tendency of electrons flowing is a conductor to flow near and on the outer surface of the conductor.

Answer 10

Skin effect

Question 11

A ___________________ circuit is made up of inductance, capacitance and resistance connected in series.

Answer 11

Series resonant

Question 12

The ____ of a series resonant circuit is the narrow frequency range over which the current is highest.

Answer 12

Bandwidth

Question 13

________ are the current levels at which the frequency response is 70.7% of the peak value of resonance.

Answer 13

Half power points

Question 14

The ________ of a series resonant circuit is the ration of inductive reactance to the total circuit resistance.

Answer 14

Quality (Q)

Question 15

________ is how a circuit responds to varying frequencies.

Answer 15

Selectivity

Question 16

The _____ circuit is formed when the inductor and capacitor of a tuned circuit are connected in parallel with the applied voltage.

Answer 16

Parallel resonant

Question 17

It is often referred to as a ______ and the circulating current is referred to as the tank current.

Answer 17

Tank ciircuit

Question 18

A ____ is a frequency selective ciircuit.

Answer 18

Filter

Question 19

___________ are created using components such as: resistor, capacitor and inductors that do not amplify.

Answer 19

Passive filters

Question 20

Use amplifying devices such as transistors and Op-Amps.

Answer 20

Active filters

Question 21

Filters only pass frequencies below a critical (cutoff) frequency.

Answer 21

Low-pass filters

Question 22

Filters only pass frequencies above the cutoff frequency.

Answer 22

High-pass filters

Question 23

Filters pass frequencies over a narrow range between lower and upper cutoff frequencies.

Answer 23

Bandpass filters

Question 24

Filters reject or stop frequencies over a narrow range between lower and upper cutoff frequencies.

Answer 24

Band-reject filters

Question 25

Filters pass all frequencies over a desired range but have a predictable phase shift characteristic.

Answer 25

All-pass filters

Question 26

Use combinations of resistors and capacitors to achieve a desired frequency response.

Answer 26

RC filters

Question 27

Use combinations of inductors and capacitors to achieve a desired frequency response.

Answer 27

LC filters

Question 28

_____________ is the loss the filter introduces to the signals in the passband.

Answer 28

Insertion loss

Question 29

________ is the resistive value of the load and source terminations of the filter.

Answer 29

Impedance

Question 30

________ is a term used to describe the amplitude variation with frequency in the passband.

Answer 30

Ripple

Question 31

____________ is the ratio of the stop bandwidth to the pass bandwidth of a bandpass filter.

Answer 31

Shape factor

Question 32

A ______ is a frequency at which there is a high impedance in the circuit.

Answer 32

pole

Question 33

____ is a term used to refer to a frequency at which there is zero impedance in the circuit.

Answer 33

Zero

Question 34

__________ or time delay is the time it takes for a specific point on an input waveform to pass through the filter.

Answer 34

Envelope delay

Question 35

_______ or attenuation rate is the rate of change of amplitude with frequency in a filter.

Answer 35

Roll-off

Question 36

The __________ filter effect has maximum flatness in response in the passband and a uniform attenuation with frequency.

Answer 36

Butterworth filter

Question 37

Has extremely good selectivity, and attenuation just outside the passband is very high, but has ripple in the passband.

Answer 37

Chebyshev filter

Question 38

Produces greater attenuation out of the passband, but with higher ripple within and outside of the passband.

Answer 38

Cauer Elliptical

Question 39

Provides the desired frequency response (i.e., low-pass, bandpass, etc.) but has a constant time delay in the passband

Answer 39

Bessel Thomson

Question 40

A _____________ uses resonant vibrations of mechanical dishs to provide the selectivity.

Answer 40

Mechanical filter

Question 41

_____________ are made of thin slivers of quartz crystal or certain other types of ceramic materials.

Answer 41

Crystal and ceramic filters