Thursday, April 1, 2010

Milestones in Electronics (Floyd and Chattopadhyay)

  • 1838 - telegraph - Samuel F. B. Morse
  • 1844 - wireless telegraphic communications
  • 1864 - James Clerk Maxwell proposed EM wave theory
  • 1876 - Alexander Graham Bell demonstrated the first voice transmission
  • 1879 - light bulb - Thomas Edison: discovered diode effect while working with VT
  • 1888 - Heinrich Hertz experimented on detection of EM radiation; he published the results in the paper entitled on electromagnetic waves in air and their reflection.
  • 1889 - first electromechanical telephone switching machine
  • 1896 - Sir J. C. Bose developed devices to generate, radiate, and receive millimeter waves.
  • 1897 - electron, CRT - Sir Joseph John Thomson
  • 1901 - patent for experimental setup of Reginald Fessenden for AM
  • 1906 - Christmas, first wireless radio broadcast - Fessenden, Brant Rock, MA
  • 1904 - Fleming valve: vacuum tube in one direction - John A. Fleming
  • 1907 - audiotron: tube with added grid that can amplify signals - Lee De Forest
  • 1912 - radio amateur in San Jose, California was able to broadcast music.
  • Regenerative amplifier - invented by Edwin Armstrong.
  • Oscillator - invented by Lee De Forest.
  • 1918 - Multivibrator was invented by Eccles-Jordan.
  • 1921 - the secretary of commerce, Herbert Hoover, issued the first license to a broadcast radio station;
superheterodyne - invented by Edwin Armstrong solved the problem for high frequency communications
  • 1923 - first TV picture tube iconoscope - Vladimir Zworykin (USA)
  • experimental demonstration of single sideband AM - R. A. Heising
  • 1925 to 1927 - J. L. Baird demonstrated actual TV (Britain)
  • 1926 - pentode - Bernard D. H. Tellegan
  • 1927 - patent for the first complete TV system - Philo T. Farnsworth
  • negative feedback - invented by Harold S. Black, Bell Laboratories
  • 1929 - pentode was introduced commercially
  • 1930s - development in radio, metal tubes, AGC, midget radios, directional antenna, etc.
  • FM - Edwin Armstrong (USA)
  • 1937 - John Atanasoff of Iowa State University envisioned a machine that can do complex math works
  • 1939 - Atanasoff and student Clifford Berry constructed binary machine called ABC (Atanasoff-Berry Computer)
  • ABC used VT for logic and capacitor for memory
  • magnetron: a microwave oscillator - Henry Boot and John Randall (Britain)
  • klystron tube - Russell and Sigurd Varian, Stanford University (USA)
  • 1940s - radar and VHF comm were made possible by magnetron and klystron
  • 1946 - ENIAC: first stored program computer - John von Neumann, University of Pennsylvania
  • 1947 - transistor - Walter Brattain, John Bardeen, William Shockley
  • printed circuits were invented
  • 1948 - 604 types - IBM
  • 1950 - Colour TV was adopted in US
  • Ebers developed SCR or thyristor
First world-wide TV was made possible by TELSTAR satellite.
  • 1951 - commercial manufacturing of transistors
  • JFET - proposed by William Shockley
  • 1954 - MASER - Charles H. Townes
  • 1958 - September 12, integrated circuit - Jack Kilby, Texas Instruments
  • Tunnel diode - L. Esaki
  • 1960s - precursors to the Internet began, ARPANET
  • LASER
  • 1960 - first MOSFET - announced by Kahng and Attla, Bell Laboratories
  • 1961 - digital IC - Buie, Pacific Semiconductor
  • 1965 - muA709, first successful op-amp, - Bob Widlar, Fairchild Semiconductor; this design suffered from latch-up
  • The 741, also from Fairchild solved the problem.
  • IMPATT - Johnston, DeLoach, and Cohen
  • 1966 - proposals of light communication via optical fiber - Kao and Hockham, Werts
  • 1969 - CCD (charge-coupled device) - Willard Boyle and George Smith, Bell Laboratories
Octopus system - 100 terminals on a computer - Lawrence Livermore, National Laboratory
  • 1970s - introduction to pocket calculators and optical ICs
  • 1970 - BJT-based RAM
  • 1971 - Intel was formed by a group from Fairchild. 4004 chip was introduced.
  • Ted Hoff - designed 4-bit microprocessor at Intel Corp.
  • 8008 - the first 8-bit microprocessor
  • 1973 - MOS-based RAM
  • 1974 - Intel 8080 - first general purpose microprocessor
Intel 80286/386/486 - 32-bit CPUs

***Computer Generations:
1st - valve-based
2md - transistor-based
3rd - IC-based
4th - VLSI architecture-based
  • 1975 - first personal computer, by Altair, featured by Popular Science in January
  • 1977 - LASER diodes using AlGaAs
  • 1978 - 64kB RAM chip
  • 1979 - Intel 8088 - 16-bit microprocessor
  • 1980s - cable hookups
  • 1990s - wide application of the Internet, e-commerce
  • 1990 - world-wide web - Tim Berness-Lee
  • 1993 - 130 websites
  • 1995 - FCC alloted spectrum space for Digital Audio Radio Service
  • 1996 - FCC adopted digital TV standards
  • 2001 - 24 million websites

Microprocessor Quiz 2

Identification.

1. The designer of 555 timers.

2. Any device that stores the status of something at a given time and can operate on input to change the status and or cause an action or output to take place for any given change.

3. Used as simplest form of error-detecting device.

4. The binary medium of communication with a computer through a designed set of instructions specific to each computer.

5. A miniaturized electronic circuit (consisting mainly of semiconductordevices, as well as positive components) that has been manufactured in the surface of a thin substrate of semiconductor material.

6. The main reason for inventing the World's forst comuter, Colossus.

7. A Japanese company that owned the rights for the first microprocessor.

8. A device or program that translates encoded data into its original format (e.g., it decodes the data).

9. They produced the first stored program computer, the first floating point machine, the first transistor computer, and the first computer to use virtual memory.

10. The designer of Intel 4004.

11. The other term for microprocessors.

12. The processor that allowed computers to more easily incorporate "real-world" data such as speech, sound, handwriting, photographic images.

13. A measure of computer's speed.

14. Microprocessor designed for gaming.

15. Microprocessor designed for MID (mobile internet devices).

16. A special purpose register that can move the bits of the word it holds left or right.

17. A special purpose register that holds an m-bit word.

18. A notation used in digital system which is equivalent to 4-bits.

19. A notation used in digital system which is equivalent to 16-bits.

20. A character-encoding scheme that represents text in computers, communications equipment, and other devices that use text.

Microprocessor Quiz

1. It is an electronic circuit that can store one bit of information.

2. It is an electronic circuit that can store one bit of memory.

3. Transparency is one of the characteristics of latches and flip-flops. This term denotes
the capability of storing and transferring information
the ability to control two or more signals
the capability to determine their output states whether it is in no change or in race condition
the ability to change at the transition of a clock signal

4. The T flip-flop is useful in constructing various types of:

5. It is the simplest example of even-parity checking:

6. These are devices that generate output based on a given input and/or a state using actions.

7. It was Intel's first microprocessor:

8. This is a type of non-volatile computer memory that uses a thin film of a magnetic material to hold small magnetized areas, known as bubbles, or domains, each of which stores one bit of data.

9. This is a a form of computer memory, similar to core memory, formed by wrapping or closing magnetic tape around a current-carrying wire.

10. It is a programmable device used to implement combinational logic circuits.

11. It is a programmable logic device with a fixed OR array and a programmable AND array.

12. It was the first general purpose electronic computer.

13. It was also manufactured as a standalone microcontroller with various configurations of on-chip RAM and EPROM.

14. IBM selects this microprocessor for their PC, introduced in August, 1981.

15. It was a 32-bit chip microprocessor and was "muti-tasking", meaning it could run multiple programs at the same time.

16. It is a smaller, faster memory which stores copies of the data from the most frequently used main memory locations.

17. It is the first 8-bit microprocessor.

18. 256 base 10 to BCD?

19. 27.35 base 16 to BCD?

20. 10011 base 2 to DEC?

21. 2132 base 5 to DEC?

22. On ASCII Table, 32 base 10 represents what character?

23. It is a measure of the ability of a logic gate output, implemented electronically, to drive a number of inputs of other logic gates of the same time.

24. It is the length of time starting from when the input to a logic gate becomes stable and valid, to the time that the output of that logic is stable and valid.

25. How many bits will you need to produce a 64K address space?

26. Which of the following is a desktop processor?
Xeon DP, Quad-core
Xeon MP, Eight-core
Itanium
Core 2 Quad

27. The first company to introduce 64-bit microprocessor to the market.

28. Which of the following microprocessors is manufactured by using CMOS technology?
Motorola 68030
IBM Power 1
Intel Pentium Pro
AMD K6

29. It is a technology that is primarily used in memory cards and USB flash drives for general storage and transfer of data between computers and other digital circuits.

30. It is a computer system technique developed, which goves an application program the impression that it has contiguous working memory (an address space), while in fact it may be physically fragmented and may even overflow on to disk storage.

Broadcasting Notes

Broadcasting - sending out sound and pictures through radio in space for the reception of the general public.

intent - general public
content - sound and pictures

Types:
Standard AM
FM
TV
International

Spectrum Regulation:
Allocation
Allotment
Assignment

Important Requirements during BC:
Timing
Fidelity
Maintain proper console signal output

Controls:
Government
Public
Industry

Leading BC station (early days):
NBC
CBC
ABC

Economics of BC:
Syndication
Public investment
Sources of fund:
  • public investment
  • advertising
  • government subsidies
  • receiver license fee
Economic pluralism
Centripetal tendency
Parsimony principle
Program balance
Generic / Thematic service
Infotainment

Components:
1. antenna
2. transmitter
3. studio
4. control room
5. auxiliary transmitter
6. complete alternate main transmitter
7. equipment repair room
8. alternate ac power equipment
9. master audio console
Unattended:
10. plate V and I final amplifier
11. modulation percentage monitor
12. antenna ammeter
13. 10-20 electrical, temperature, and security parameter scanned several times - CRT monitor
14. remote program pickup (NR)
15. network program (LMS)
16. remote pickup broadcast station
17. aural broadcast STL station
18. aural BC intercity relay station

Requirements for new BC:
1. File petition CPCN
2. Public hearing
3. NTC decision

Communications Review

RA # 9292 - Electronics Engineering Law of 2004; April 17, 2004; Effective May, 2008
Communications is the process of sending and/or receiving data, signals, and/or messages between two or more points by radio, cable, optical waveguides, or other devices, and wired or wireless medium.

The goal of communications system is to transfer information from one place to another.

Classes of Communications System:
Simplex
Half-Duplex
Full-Duplex

Inventions:
Telephone - 1876
Radio - 1894
TV - 1945
Internet - 1994, Sputnik

Telephony:
1st - used bell, speaker, and earpiece
It was called Butterstamp telephone
Rotary-dialed phone - 500 type telephone set; pulse dialing
Push-button dial phone - 2500 type
Modern telephone set - uses caller ID

There were only 6 telephones back then.
1st patent - Alexander Graham Bell
telephone switchboard - Tivaidar Puskas
1st patent for caller ID - Theodore George Paraskevakos (Athens, Greece)

PSTN - public switched telephone network; generic term for domestic public telephone network; largest and best known traffic network
network - system of interconnected elements
telecommunications network - network of interconnected elements designed to carry telecommunications services
traffic - flow of messages

2 compositions of PSTN:
inside plant
outside plant

CPE - customer premise equipment; not part of PSTN because it is private, therefore not part of the network

Types of CPE:

telephone set
modem
PBX

Transmission facilities:
lines - communications path from CPE to SO (switching office)
trunk - connection between two switching offices.
special service curcuit (SSC) - provides special service to specific customers

*POTS
- plain old telephone system
*switching office - also called central office; provides connection between customer line and switching facilities
*tandem office - an exchange without loops connected to it. The only facilities connected to the switching machine in a tandem office are trunks.

When a subscriber initiates a long distance call, the local exchange connects the caller to a toll office through a facility called a toll-connecting trunk (interface toll trunk).

Area codes/country codes are used because tandem offices are only used for local calls.

IGF - international gateway facility

Gibilisco Quiz 2

1. A positive electric pole:
A. Has a deficiency of electrons.
B. Has fewer electrons than the negative pole.
C. Has an excess of electrons.
D. Has more electrons than the negative pole

2. An EMF of one volt:
A. Cannot drive much current through a circuit.
B. Represents a low resistance.
C. Can sometimes produce a large current.
D. Drops to zero in a short time.

3. A potentially lethal electric current is on the order of:
A. 0.01 mA.
B. 0.1 mA.
C. 1 mA.
D. 0.1 A.

4. A current of 25 A is most likely drawn by:
A. A flashlight bulb.
B. A typical household.
C. A power plant.
D. A clock radio.

5. A piece of wire has a conductance of 20 siemens. Its resistance is:
A. 20 Ω.
B. 0.5 Ω.
C. 0.05 Ω.
D. 0.02 Ω.

6. A resistor has a value of 300 ohms. Its conductance is:
A. 3.33 millisiemens.
B. 33.3 millisiemens.
C. 333 microsiemens.
D. 0.333 siemens.

7. A mile of wire has a conductance of 0.6 siemens. Then three miles of the same
wire has a conductance of:
A. 1.8 siemens.
B. 1.8 Ω.
C. 0.2 siemens.
D. Not enough information has been given to answer this.

8. A 2-kW generator will deliver approximately how much current, reliably, at 117
V?
A. 17 mA.
B. 234 mA.
C. 17 A.
D. 234 A.

9. A circuit breaker is rated for 15 A at 117 V. This represents approximately how
many kilowatts?
A. 1.76.
B. 1760.
C. 7.8.
D. 0.0078.

10. You are told that a certain air conditioner is rated at 500 Btu. What is this in
kWh?
A. 147.
B. 14.7.
C. 1.47.
D. 0.147.

11. Of the following energy units, the one most often used to define electrical
energy is:
A. The Btu.
B. The erg.
C. The foot pound.
D. The kilowatt hour.

12. The frequency of common household ac in the U.S. is:
A. 60 Hz.
B. 120 Hz.
C. 50 Hz.
D. 100 Hz.

13. Half-wave rectification means that:
A. Half of the ac wave is inverted.
B. Half of the ac wave is chopped off.
C. The whole wave is inverted.
D. The effective value is half the peak value.

14. In the output of a half-wave rectifier:
A. Half of the wave is inverted.
B. The effective value is less than that of the original ac wave.
C. The effective value is the same as that of the original ac wave.
D. The effective value is more than that of the original ac wave.

15. In the output of a full-wave rectifier:
A. The whole wave is inverted.
B. The effective value is less than that of the original ac wave.
C. The effective value is the same as that of the original ac wave.
D. The effective value is more than that of the original ac wave.

16. A low voltage, such as 12 V:
A. Is never dangerous.
B. Is always dangerous.
C. Is dangerous if it is ac, but not if it is dc.
D. Can be dangerous under certain conditions.

17. Which of these can represent magnetomotive force?
A. The volt-turn.
B. The ampere-turn.
C. The gauss.
D. The gauss-turn.

18. Which of the following units can represent magnetic flux density?
A. The volt-turn.
B. The ampere-turn.
C. The gauss.
D. The gauss-turn.

19. A ferromagnetic material:
A. Concentrates magnetic flux lines within itself.
B. Increases the total magnetomotive force around a current-carrying wire.
C. Causes an increase in the current in a wire.
D. Increases the number of ampere-turns in a wire.

20. A coil has 500 turns and carries 75 mA of current. The magnetomotive force
will be:
A. 37,500 At.
B. 375 At.
C. 37.5 At.
D. 3.75 At.

Communications Quiz

1. Electronic communications was discovered in which century?
sixteenth
eighteenth
nineteenth
twentieth

2. What is the standard for wireless technology known as Bluetooth?
IEEE 802.15
IEEE 802.11b
IEEE 802.11a
IEEE 802.20

3. When the first symbol in the FCC signal classification is J, it means:
having an amplitude modulated single sideband suppressed carrier
having a frequency modulated main carrier
having an unmodulated main carrier
having an amplitude modulated single sideband full carrier

4. The ratio of the peak modulating signal voltage to the peak carrier voltage is referred to as:
modulation index
modulation coefficient
both a or b
neither a or b

5. ASCII code has how many bits?
4
7
5
8

6. The IEEE standard use for high speed wireless Ethernet access known as Wi-Fi is
803.12
803.11b
802.11b
802.11

7. What is the first symbol of a radio signal emission having an amplitude modulated main carrier, double sideband?
C
H
B
A

8. All electronic components except one below generate noise:
resistor
capacitor
transistor
diode

9. What is the reference temperature used in noise analysis?
75-K
290-K
250-K
300-K

10. The solar cycle repeats the period of great electrical disturbance approximately every:
11 years
9 years
10 years
8 years

11. For ideal AM, which of the following is true?
m = 0
m = 1
m < 1
m > 1

12. The outline of the peaks of a carrier has a shape of the modulating signal is called:
trace
waveshape
envelope
carrier variation

13. Overmodulation occurs when
Vm > Vc
Vm < Vc
Vm = Vc
Vm = Vc = 0

14. The value of Vmax and Vmin as read from an oscilloscope are 2.8 and 0.3 respectively. The percent of modulation is
10.7
41.4
80.6
93.3

15. A carrier of 880-kHz is modulated by a 3.5-kHz sine wave. The LSB and USB are ___ and ___ respectively.
873- and 887-kHz
876.5- and 883.5-kHz
883.5- and 876.5-kHz
887- and 873-kHz

16. For 100% modulation, what percentage power is in each sideband?
25%
33.33%
50%
100%

17. In an AM signal, the transmitted information is contained within the
carrier
modulating signal
sideband
envelope

18. Amplitude modulation can be produced by
having the carrier vary in amplitude
having the modulating signal vary in amplitude
having the carrier vary in frequency
having the modulating signal vary in frequency

19. Noise is primarily
high frequency spikes
low frequency spikes
random level shifts
random frequency variations

20. The noise voltage across the 300-ohm input resistance to a TV set with 6-MHz bandwidth and an ambient temperature is:
2.3-mV
3.8-uV
5.4-uV
6.4-nV

21. A transmitter radiates a total power of 10-kW. The carrier is modulated to a depth of 60%. Calculate the power in the carrier and each sideband.
687- and 345-W
856- and 876-W
788- and 894-W
847- and 762-W

22. Noise at the input to a receiver can be as high as several
uV
mV
nV
V

23. Which of the following is not a source of external noise?
thermal agitation
audio ignition
sun
fluorescent light

24. Noise can be reduced by:
widening the bandwidth
narrowing the bandwidth
increasing the temperature
increasing the resistance level

25. An AM signal with a maximum modulating frequency of 4.5-kHz has a total bandwidth of
4.5-kHz
6.75-kHz
9-kHz
18-kHz