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1

1-1 Metallica media – general

Volts, amp, ohm =

V, A, (ohm)

2

1–2 electrical conductors

Common electrical conductor =

Except fiber or silver alloy (does not belong)

3

1–2 description of conductors

Copper =

(2)

 

* Annealed copper

* 100% conductivity

4

1–2 description of conductors

Alloy Copper =

Adverse conductivity

5

1–3 solid conductor properties

Aluminum corrosion resistance =

Aluminum oxidation resistance =

 

* Good

* poor

* and vice versa for High-strength alloys

6

1–4 solid vs stranded conductors

Advantages solid conductors =

Better transmission

7

1–4 solid vs stranded conductors

Advantages stranded conductors =

(2)                   ^

* more flexible

* except better transmission (does not belong)

8

1–5 AWG intro

AWG =

(2)

* American wire gauge

* accepted in North America

9

1–5 insulation intro

PVC =

PE =

* Inside

* OSP

10

1-5 insulation intro

a dielectric prevents direct contact = 

(2)

 

* conductors

* a conductor and its environment

11

1–6 insulation intro

Teflon trademark =

du Pont

12

1–6 insulation intro

FEP trademark =

Daikin

13

1–6 insulation intro

Halar trademark =

Solvay

14

1–7 insulation electrical characteristics

Dielectric strength =

Measures maximum voltage

15

1–8 balance twisted pair cable

Twisting pairs =

Minimize Crosstalk

16

1–8 balance twisted-pair cable

Capacitance =

Electrical field

17

1–8 balance twisted-pair cable

Mutual inductance =

Measure magnetic field

18

1-8 balance twisted-pair cable

Pair twists =

Counterclockwise

19

1–8 balance twisted-pair cable

Tight twists =

Preserves cable shape

20

1–9 environmental considerations – temperature

Balance twisted-pair cable =

Increased attenuation above 68°F

21

1–9 environmental considerations – temperature

High temperatures in =

(3)

* Exterior

* ceilings

* mechanical rooms

22

1-14 types of shields

Shields =

Except fiber related, does not belong

23

1-14 types of shields

Solid wall metal tubes (conduit) =

 

Best possible shield

24

1–15 types of cable

Braid shield =

(2)

 

* audio = good

* magnetic field = poor

25

1–15 types of cable shields

Foil shield =

 

Excellent

26

1–15 shield effectiveness

Poor =

Excellent =

 

* Less than 20 dB

* more than 60 dB

27

1–15 shield effectiveness

Permeability =

 

Magnetic substance

28

1-16 drain wires

Shield not properly grounded =

 

Effectiveness reduced

29

1-16 drain wire applications

Drain wire =

 

Longitudinally

30

1-17 analog signal intro

Analog =

(2)

* wave

* example - sinusoid

31

1-18 sinusoidal signal

Human hearing =

20 Hz to 20,000 Hz

32

1-18 sinusoidal signal

Voice circuits =

300 to 3400 Hz

33

1-18 sinusoidal signal

Kilohertz =

1000 Hz

34

1-19 sinusoidal signal

Phase =

 

Time

35

1-19 sinusoidal signal

One cycle =

 

360 degrees

36

1-20 sinusoidal signal

Sinusoidal theorem =

Joseph Fourier

37

1-21 decibel (dB)

If you have one watt of power on your input and one watt on your output, what is the total amount lost in dB?

1000

 500 = 3

 250 = 3

 125 = 3 

  62.5 = 3

  31.25 = 3

  15.625 = 3

   7.8125 = 3

   3.90 = 3

   1.95 = 3

    .97 = 3

          = 30dB

              ^

38

1-22 decibel dB

Doubling power =

 

+3dB

39

1-22 decibel dB

1/2 power =

 

-3dB

40

1-22

Phenomenon =

 

Echo

41

1-23 telephony

Telecom transmission system =

(3)

* source energy

* medium to carry

* receiving

42

1-23 telephony

Same load =

 

Same impedance

43

1-24 telephony

600 ohm impedance

 

Private line circuits

44

1-24 telephony

900 ohm impedance

Central office circuits

45

1-24 telephony echo

Speed of light =

186,000 mi/s

46

1-24 telephony echo

Speed of light in cable =

Or EM radiation slows

.56c to .74c

47

1-24 telephony echo

Satellite delay =

1/4 (0.25) second

48

1-25 telephony distortion

D loading =

H loading =

* 4495ft

* 6004ft

49

1-28 IP telephony

VIOP power source =

 

Except bridge, does not belong

50

1-29 digital signals

Digital signals =

 

Discrete steps

51

1-29 digital signals

Analog to digital =

 

4th step - companding

52

1-30 analog-to-digital

Analog sampling theorem =

 

Harry Nyquist

53

1-30 analog-to-digital

Companding =

(2)

 

* A-law - Europe

Mu-law - United States, Canada, Japan

54

1-30 digital signal

PCM =

(2)

 

* pulse code modulation

* 256 levels

55

1-30 PCM

8000 samples/s x 8 bits / sample =

How many levels?

 

64,000 b/s

56

1-31 PCM

Codecs =

 

Conversion of speech

57

1-31 TDM

TDM = 

(3)

 

* Time Division Multiplexing

* combines binary data

* combines multiple data streams

58

1-33 TDM

E1 frame format

(8 b/x channel x 32 channels) x 8000 frame/s = 

 

2.048 Mb/s

59

1-34 encoding

Encoding methods =

(2)

 

* AMI = alternate mark inversion; bipolar

* Manchester = +\- equal intervals; biphase

60

1-35 digital data to digital signal

Baud (rate) =

 

Modems

61

1-36 digital data to digital signal

Coding method STS-1 =

 

51.8 Mb/s

62

1-36 digital data to digital signal

Coding method STS-3 =

 

155 Mb/s

63

1-36 digital data to digital signals

Coding method:

ISDN (basic) =

ISDN (primary) =

 

* 160 Kb/s

* 1.544 Mb/s

64

1-41 types of transmission circuits

Transmission circuits =

(3)

 

* Simplex = one direction

Half-duplex = both directions one at a time

* full-duplex = both directions at the same time

65

1-42 asynchronous and synchronous transmissions

Asynchronous =

 

Start and stop

66

1-42 asynchronous and synchronous transmission

Synchronous =

(2)

 

* more efficient

* single master clock

67

1-43 digital hierarchy

Basic ISDN =

Residential

68

1-43 digital hierarchy

Primary ISDN North America =

(4)

* large business

* 1.544 Mb/s

* 23 B channels

* 1 D channel

69

1-43 digital hierarchy

Primary ISDN Europe =

(4)

* large business

*2.048 Mb/s

* 30 B channels

* 1 D channel

70

1-44 HSDL

HSDL = 

(2)

 

* high bit-rate digital subsciber line

* DS1 over balananced twisted pair

71

1-44 SDSL

SDSL =

(2)

 

* Symmetircal digital subscriber line

* single pair version of HDSL - DS1 over 1pr balanced twisted pair cable

72

1-49 video transmission

Baseband signaling =

(2)

 

Composite and component

73

1-50 video transmission

Component format RGB =

 

Red, green, blue

74

1-51 broadband video

RF carrier=

 

Represents a TV channel

75

1-51 Balanced twisted pair media implementation

tradititional video transmission = 

 

coax and fiber

76

1-51 Balanced twisted pair media implementation

Broaband analog CATV = 

 

Category 5e or higher

77

1-53 transmission line concepts

Conductance (G) =

 

Represents leakage

78

1-53 Figure 1.16

 

 

resistive model

79

1-55 Figure 1.18

 

 

 

 

Inductive Model

80

1-59 transmission line concepts

Crosstalk =

 

Signal interference

81

1-59 transmission line concept

NVP =

(2)

 

* percentage of the speed of light

* .62c

82

1-59 transmission line concept

Balance twisted-pair cables =

 

.56c to .74c

83

1-60 transmission line concept

Delay skew =

(2)

 

* difference in propagation delay

* not to exceed 45ns

84

1-61 signal-to-noise ratio (SNR)

Q= 10mW signal input lead and 10 microwatts of noise 1 dB of loss per 100ft in a 1000ft run. What is rage SNR?

 

20dB

SNR (dB) = 20 log

( Vo / Vn) = 20 log (Vi / Vo)

Vo = received signal voltage level

Vn = noise signal voltage level at the receiver

Vi = transmitted signal voltage level

85

1-61 transmission line concepts

ACR =

(2)

 

* Attenuation to Crosstalk ratio

* minimum NEXT loss - maximum attenuation

86

1-62 Return loss

better impedance matching = 

 

lower reflected engery and higher return loss

87

1-62 Return loss

 

Return loss = 

 

derived from reflection coefficient

 

 

88

1-62 Return loss

mismatched impedance = 

 

signal reflectoins (echoes)

89

1-63 balance twisted-pair performance

Balance twisted pair cables =

Impedance of 100 ohms

90

1-72 balance twisted-pair applications

ANSI/TIA/EIA-232-F =

^

ANSI/TIA/EIA-422-F = 

^

 

* 150ft

 

* 50ft to 4000ft 

91

1-72 balance twisted-pair applications

DS1 rate =

 

2 twisted-pair

92

1-72 balance twisted-pair applications

100BASE – T4 =

 

4 twisted-pair

93

1-72 balanced twisted-pair applications

10GBASE-T =

 

4 twisted-pair

94

1-75 Shared Sheath Applications and Compatibilty

No more than 12 10BASE-T =

 

in the same binder group

95

1-76 balanced twisted pair applications

Baluns =

(3)

 

* impedance matching device

* twisted-pair to coaxial and coaxial to twisted-pair

* UTP to coaxial

96

1-77 Signal Converters

Advantages = 

(2)

 

* decrease EMI problems

* extend DTE signal reach

97

1-79 optical fiber intro

Simple model of telecom systems =

(3)

* transmitter

* receiver

* medium

98

1-80 optical fiber transmitters

850 nm/1300 nm = 

1310 nm/1550 nm = 

 

* Multimode (mm)

* singlemode (SM)

99

1-86 optical fiber transmitters

VCSEL =

 

Vertical cavity surface emitting laser

100

1-86 optical fiber transmitters

VSCEL advantages =

(2)

* cost-effective mm transmitter for gigabit ethernet and fibre channel

* 10Gigabit and fibre channel

101

1-90 optical fiber medium

Core size selection =

(3)

* active equipment

* distance

* bandwidth (data rate)

102

1-91 optical fiber medium

                 Type   Bandwidth

OM1 =

OM2 =

OM3 =

* 62.5um MM 200 & 500MHz/km

* 50um MM 500 & 500MHz/km

* 50um laser, VSCEL 2000 &500MHz/km

103

1-91 Optical fiber media

OS2 =

 

Low-water peak

104

1-92 balance twisted-pair channel performance

ISO Class C =

ISO Class D =

 

* Cat3, 16MHz

* Cat5e, 100MHz

105

1-98 optical fiber bandwidth

Dispersion =

(3)

* bandwidth limitations

light pulse to broaden

* measured in picoseconds (psec)

106

1-99 optical fiber bandwidth

Chromatic dispersion =

 

Multimode

107

1-102 Optical fiber bandwidth

Classifications of fiber =

MM & SM

108

1-102 optical fiber bandwidth

MM 1Gb/s =

1804ft

109

1-106 optical fiber bandwidth

Visible light wavelengths =

 

400nm to 700nm

110

1-106 optical fiber bandwidth

wavelength =

 

Windows

111

1-107 optical fiber bandwidth

SM loss value =

(2)

 

* outside cable .5dB

* inside cable 1.0dB

112

1-109 optical fiber application support

12 connectors x 0.75dB =

6 connectors x 0.75dB =

 

* 9.3

* 4.8

113

1-109 optical fiber application support info

Maximum attenuation for

50um mm =

62.5um mm =

Singlemode (OSP) =

 

* 3.5dB & 1.5dB

* 3.5dB & 1.5dB

* 0.5dB & 0.5dB

114

1-116 attenuation

Power penalty for:

LED's =

Lasers =

 

* 2dB

* 3dB

115

1-116 attenuation

Power penalty for repair margin =

 

Two repair splices

116

1-118 attenuation

Temperature changes =

 

2dB/km

117

1-118 attenuation

Maximum connection loss =

Maximum splice loss =

 

* 0.75dB

* 0.3dB

118

1-118 vattenuation

Splice loss for fusion:

MM & SM =

 

Max 0.3dB

119

1-118 attenuation

Splice loss of mechanical:

MM & SM =

 

Max 0.3dB

120

1-118 attenuation

Fusion =

Mechanical =

*permanent, 0.3db

* emergency/temporary, 0.3db

121

1-122 optical fiber SONET & SDH concepts

SONET =

Synchronous optical network

122

1-122 optical fiber SONET & SDH concepts

SDH =

Synchronous digital hierarchy

123

1-122 optical fiber SONET & SDH concepts

STS-1/OC-1 =

 

* 51.84 MB/s

* 672 voice channel

124

1-122 optical fiber SONET & SDH concepts

STS-3/OC-3 =

 

* 155.52 MB/s

* 2016 voice channels

125

1-122 optical fiber SONET & SDH concepts

STS-12/OC-12 =

622.08 Mb/s

8064 voice channels

126

1-123 Figure 1.30

mux =

DSX =

 

* multiplexing

* digital signal cross-connect

 

127

1-124 optical fiber SONET & SDH concepts

WDM =

(2)

 

* wavelength division multiplexing

* uses lenses

128

1-124 optical fiber SONET & SDH concepts

WDM lenses =

Refract and direct light

129

1-129 North American digital signal

DS1 =

DS1C =

DS3 =

* 24 channels

* 48 channels

* 672 channels