255 Items
1. It is the scientist
who is engaged in the study in the field of acoustics
Acoustician
2. Who coined the term
"cyberspace?"
William Gibson
3. For educational
purposes, who is the person who first discovered/ invented the telephone?
Antonio Meucci
4. What is the frequency
of the middle C?
262 Hz
5. What is the frequency
of the upper side/ above middle C?
524 Hz
6. It is the loudness
level (in PHON) of a watch ticking.
20 PHON
7. What is the maximum
limit time of exposure on sound levels between 100 dB and 110 dB?
20 minutes
8. What is the
colloquial name for the term "Thin Ethernet"?
Cheapernet
9. Local Multipoint
Distribution Service (LMDS) operates at what frequency range?
27 - 31 GHz
10. A video signal that
has no sync signal is what you called
Non-composite
Video Signal
11. It is the gas that
is used in jet engines.
Hydrazine
12. A satellite is put
into final geosynchronous orbit from its transfer orbit by firing the
__________.
apogee kick
motor
13. A terrestrial
communications channel linking an earth station to a local switching network or
population center
Backhaul
14. Polytetrafluoroethylene
is also known as
Teflon
15. For SSB transmitter,
the average power is typically __________ of the peak envelope power, with a
typical human speech
1/4 to 1/3
16. It is often called
text messaging, is a means of sending short messages to and from mobile phones.
The Short
Message Service (SMS)
17. North American type
of sound files as a substitute for MP3
AC-3 Dolby
18. A table showing the
pre-calculated position of satellite at any given time
Ephemeris
19. How many Horizontal
scanning lines are there in HDTV?
1125
20. How long that a GPS
satellite completes its orbit?
12 hrs
21. What is the other
term for parity check?
Vertical
Redundancy Check
22. What is the other
name for single button microphone?
Carbon Button
23. Instrument that is
used in measuring the virtual height of ionosphere
Ionosonde
24. An instrument used
to measure relative height, layers in the ionosphere regarding wave
propagation?
Ionosonde
25. In a trapezoid
modulation, 100% modulation will result to what waveform?
triangular
waveform
26. It is the type of
navigation that is based in Newton's Law of motion
Inertial
Navigation System
27. What type of
navigation system that currently used in aircraft, submarines, spacecraft and
guided missiles.
Inertial
Navigation System
28. What is the
successor of Bluetooth?
Lisbon
29. What is the
successor of Bluetooth after Lisbon?
Seattle
30. Carrier freq is also
known as
rest freq
31. Who developed the
superheterodyne receiver
Edwin Armstrong
32. When the angle of
incidence is equal to the angle of refraction, the light in the fiber optics is
in what direction
along the normal
path
33. What refers to the
sampling of analog signal using a sample and hold circuit, such that the sample
has the same amplitude for its whole duration
flat top sample
34. What is the antenna
height of a CB (Citizen Band) radio?
60 ft above the
ground and 20 above the building
35. What is the nearest
star in the solar system
proxima centauri
36. A rocket has two
satellites, the smaller will continue to propel in the space after the bigger
satellite has been launched. What do you call this bigger satellite?
initial payload
37. What antenna is used
in radar?
horn with
parabolic reflector which rotates 360 degree
38. What is the distance
which needs a repeater in the microwave communication?
40 km
39. Terrestrial
microwave antennas has an input and output impedance of ________ ohms.
50
40. Radio format that
uses Mpeg 4 video compression
Divx
41. What is the typical
value of velocity factor of an open wire transmission line?
0.9
42. Type of resistor use
to reduced flicker noise voltage (0.02 to 0.2 mV)
metal film
43. In 2002, a standard
for (BWA) Broadband Wireless Access was introduced and in the IEEE standard it
is more commonly known as 802.16. This also refers to
WiMax
44. The current digital
video specification that used video compression
MPEG 4
45. 802.15.4 is also
known as
Zigbee
46. In radio
communication, what is the point on a line between the earth’s center and an
observer, located further from the earth’s center on a point?
Nadir
47. A camera tube that
is formed from lead oxide (PbO)
Plumbicon
48. What part of visible
spectrum where camera pick up that has the greatest output?
Yellow Green
49. In a telephone
channel, if the total via net loss of a given trunk circuits exceeds
approximately 2.5 dB, a device known as ___________ is inserted.
Echo Suppressor
50. In CMTS, the
frequency separation between forward and reverse channel is
45 MHz
51. Helical antennas are
often used for satellite tracking at VHF because of the
Faraday Effect
52. What formula is used
to calculate the overall noise performance if receiver or of multiple state of
RF amplification?
Friis Formula
53. What is IEEE
standard for WiFi?
802.11b
54. High definition TV
picture contains about _____ as much info as the present NTSC TV.
5 times
55. Communication
antenna used with rotating satellite which the antenna is continuously adjusted
with respect to the satellite so that the antenna illuminates a certain part of
the earth surface.
Despun antenna
56. An acoustic scale
whose intervals are exactly consonant
diatonic
57. What is the typical
value of velocity factor of a twin lead transmission line?
0.8
58. What is the typical
value of velocity factor of an open wire transmission line?
0.9
59. Radio blackout on
the entire sunlit side of the Earth lasting for a number of hours
R5
60. Severe HF radio
communications blackout occurs mostly on the sunlit side of Earth for one to
two hours
R4
61. A wide area blackout
of HF radio communication as well as loss of radio contact for about an hour on
the sunlit side of Earth.
R3
62. Moderate limited
blackout of HF radio communications on sunlit side occur, loss of radio contact
for tens of minutes
R2
63. Limited blackout of
HF radio communications on sunlit side occur, loss of radio contact in an
occasion.
R1
64. What is the orbital
time of MEO satellite?
5 to 12 hrs
65. Is the process by
which a permanent, low-loss, high strength, welded joint is formed between two
optical fibers?
fusion splicing
66. Involves many
different approaches for bringing the two ends of the fibers into alignment and
then clamping them within a jointing structure or gluing them
together__________
mechanical
splicing
67. With this method,
the signal modulates a carrier that is linearly swept over the band being used
chirp
68. One bit time for the
pseudorandom code is called a
chip
69. What is the last
amplifier stage of ______________ amplifier?
power amplifier
70. A submarine at
greater depth can deploy a ______________ about 2.000 feet long, but 200 feet
of it must float on the surface for proper reception
trailing wire
antenna
71. The typical excess
noise (flicker noise) for carbon resistor?
0.1μV to 3.0 μV
72. The typical excess
noise (flicker noise) for carbon film resistor?
0.05 μV to 0.3
μV
73. The typical excess
noise (flicker noise) for metal film resistor?
0.02 μV to 0.2
μV
74. What is the typical
excess noise (flicker noise) for a wire-wound resistor?
0.01 μV to 0.2μV
75. EDGE produces a
3-bit word for every change in carrier phase
76. Bit stuffing in the
HDLC protocol works by transmitting on the sending side five consecutive 1's
from the body of the message and by inserting 0 before transmitting the next
bit.
77. Magic T is also
known as
hybrid T
78. It is the satellite component that senses the time
or the incidence angle of solar radiation and provides electrical signal that
may be used to compute the satellite orientation?
sun sensor
79. A few centimeters
long solid insulated hook up wire that provides small capacitance to the ground
that is adjusted during circuit alignment by bending slightly in one direction
or another.
gimmick
80. The maximum
radiation for electronic equipment must not exceed ____________ mr/week
100
81. Radiation exposure
rates produced by a TV receiver shall exceed ______________ milli roentgens per
hour at a distance of 5 cm from any point on external surface of the receiver
0.5
82. What expresses the
steepness of the skirts or the skirts selectivity of a radio receiver?
shape factor
83. Standard signal
format of a numeric paging receiver
NEC D3 standard
84. The critical
capacitance variation of most varactors used in frequency modulators
12 to 1
85. If the satellite is
launched at the speed of exceeding 25000 mph the satellite will not go in orbit
and will break away from the gravitational pull of the earth and go out in deep
space
space probe
86. What is the voltage
of the local loop on hook?
-48 Vdc
87. In a propagation
medium such in the glass of an optical fiber __________ is the scattering of
the electromagnetic wave by particles with the size about equal or greater than
the wavelength
MIE scattering
88. What LED is usual
signal source for plastic fiber?
red LED
89. In color CRT, what
refers to adjustment of the three electron beam so that each lens can phosphor
dots on the appropriate color?
purity
90. What is considered
as the simplest transmitter keyed on and off to produce CW Morse code?
oscillator
91. How many orbital
planes which are equally spaced around the equator in GPS operational constellation?
6
92. What may cause ionic
disturbance characterized by rapid cluttering sound hence voice communication
is poor?
Aurora borealis
93. The mandatory 24
ship-to-shore communications from 1910 to 1912 was the establishment by the US
Great Britain and other maritime nation as the direct result of the sinking of
the 2 famous ships
The Republic and
Titanic
94. When the called
telephone is ringing , the Central Office sends a pulse AC voltage to the
calling telephone. What is the signal called?
Ringback signal
95. What is the main
accelerating element in CRT?
Ultor
96. IN analog cellular
system, the interfering signal strength remains approximately less than __ of
desired signal strength to assure negligible interference
2%
97. What is the
approximate critical frequency of E layer?
4 MHz
98. What is the
approximate critical frequency of F 2layer?
8 Mhz
99. The 10 base T-Ethernet
system is restricted only to __________.
100m
100. What is the code
used in 100 Mbps Tx Ethernet standard?
3 level
Manchester code
101. Principal musical
intervals is considered dissonant
7:8
102. Cell site center
that is mounted on a flat bed tractor used for emergency purposes
COW
103. Geographic distance
that is required between cells used in identical frequencies in order to avoid
interference between the radio transmissions of these cells
Distance to
reuse ration D/R
104. Random data sent
continuously by the NIC that disrupts the whole area network
Jabber
105. Shifting of antenna
pattern so that the major lobe is at angle below the horizontal
down tilt
106. Term used to
describe ordinary voice telephony
Plain Old
Telephone Service (POTS)
107. Time period for
a single time slot in the GSM TDMA structure
8
108. The first note of
the musical scale
Root note
109. In CATV system,
what is the output RF terminal match?
16 dB
110. Dielectric constant
of polyethylene insulator
2.27
111. How much more feed
point Z does a folded dipole have than a normal dipole?
4 times
112. In TV system, if
the 3.58 MHz C amplifier in the receiver does not operate, the result will be
__________.
No color
113. Allows users to
access documents from widely separated sources of the internet using a common
source
World Wide Web
114. What is the typical
value of line turn around?
1.5 ms
115. Which pulse in the V BLANKING corresponds to 3H lines wide?
V sync
116. F3 emission means
carrier is frequency modulated by ____________.
voice
117. How many horizontal
lines are blanked out in the frame of TV receivers by V BLANKING?
42
118. Which one is a
non-continuous noise?
Impulse noise
119. What is the refresh
rate in PAL?
50 Hz
120. BISYNC is found on
what layer?
Data link layer
121. In Precise
Positioning Service (PPS) of a GPS positioning service, what is the horizontal
PPS Predictable Accuracy?
22 meters
122. In Precise
Positioning Service (PPS) of a GPS positioning service, what is the vertical
PPS Predictable Accuracy?
27.7 meters
123. In Precise
Positioning Service (PPS) of a GPS positioning service, what is the time (UTS)
PPS Predictable Accuracy?
200 nanoseconds
124. In Standard
Positioning Service (SPS) of a GPS positioning service, what is the horizontal
SPS Predictable Accuracy?
100 meters
125. In Standard
Positioning Service (SPS) of a GPS positioning service, what is the vertical
SPS Predictable Accuracy?
156 meters
126. In Standard
Positioning Service (SPS) of a GPS positioning service, What is the time (UTS)
SPS Predictable Accuracy?
340 nanoseconds
127. A three-minute
music file that is compressed into MP3 format will have a file size of
3 Mb
128. A three-minute
music file that is compressed into WAV format will have a file size of
30 Mb
129. In the IMT 2000
system standard, what does "2000" mean?
both means the
year that the system is implemented and its approximate frequency assignment
130. It is a table
showing the pre-calculated position of satellite at any given time
Ephemeris
131. What is the
currently used internet protocol?
IPv4
132. This internet
protocol has much larger address space that allows greater flexibility in
assigning addresses and is able to support 128 bit of addresses.
IPv6
133. What helps protect
fiber against degradation caused by moisture?
Cabling
134. In cellular system,
typically how many cells in the frequency reuse plan format?
7
135. What is the typical
beam width of horn antenna?
10 degrees to 60
degrees
136. In acoustics, what is the pleasant combination of sound intervals?
Consonant Interval
137. In acoustics, what is
the unpleasant combination of sound intervals?
Discordant
Interval
138. Refers to any sonic,
infrasonic or ultrasonic wave which is emitted from electronic product as a
result of the operation of an electronic circuit in such product
Radiation
139. What is the science of
measuring light that is visible to the human eye?
Photometry
140. What is the typical
range of vidicon dark current?
0.2 uA
141. What might be the
typical range of mobile-to-mobile?
1 to 10 miles
142. What is the typical
noise figure of FET and MESFET used at microwave frequency?
2 dB or less
143. Why does a high Q
circuit discriminate against harmonics?
because of purer
sine wave ac
144. What do you call the
portion of the horizontal blanking pulse before the sync pulse?
Front Porch
145. What is the typical
bandwidth of single mode step index fiber?
50 to 100 Ghz/km
146. RF radiation damage cells of reproductive tissues
Genetic
147. RF radiation
damage to other than the cells of reproductive tissues
Somatic
148. HDTV is in
rectangular form and contains ___________ times more information than the
current TV.
5
149. In radio
communication, what do you call a point on a line, between the earth's center
and an observer, located farther from the earth center than point?
Nadir
150. The velocity
of geostationary orbit satellite is
6879 statute
miles per hour
151. Cable TV
companies collect signals and programs from many sources in a facility called
__________.
Head End
152. What is the maximum power rating of CB (Citizens Band) J3E transmitter?
4W
153. What is the
maximum power rating of CB (Citizens Band) A3E transmitter?
12W PEP
154. If mobile
phone loses its signal, the transmitter will retransmit after
1 to 5 seconds
155. How far must
the distance between the microphone and the mouth of the user?
2 inches
156. It is a device
used to measure an individual's exposure to a hazardous environment
Dosimeter
157. A system where
cables and wires are placed within the ceiling space and poked up through the
fire resistant floor structure to the office or room above
Poke Through
158. The typical
transmit power for cellsite is
10 W to 50 W
159. What is the
effective height of the antenna?
1/2 to 2/3 of
the actual height of the antenna
160. A signaling
path provided by a cable television system to relay to subscriber terminals
television broadcast programs that are received off-the-air or are obtained by
microwave or by direct connection to a television broadcast station.
Class I Cable
Television Channel
161. A signaling
path provided by a cable television system to deliver to subscriber terminals
television signals that are intended for reception by a television broadcast
receiver without the use of an auxiliary decoding device and which signals are
not involved in broadcast transmission path.
Class II Cable
Television Channel
162. A signaling path provided by a cable television
system to deliver to subscriber terminal signals that are intended for
reception by equipment other than a television broadcast receiver only when
used with auxiliary equipment.
Class III Cable
Television Channel
163. A signaling
path provided by a cable television system to transmit signals of any type from
a subscriber terminal to another point in the cable television system.
Class IV Cable
Television Channel
164. Which of the
following identifies the maximum transmitted power level of a mobile phone?
Station Class
Mark (SCM)
165. Why tropospheric ducting is not used very much in practical communication system?
because it is
not reliable
166. Which of the
following is the last stage of the AM transmitter?
PA (Power
Amplifier)
167. What is the
efficiency of the parabolic antenna?
55%
168. What is the total
noise in the absence of the information (intelligent signal)
Background noise
169. What is the
data rate of enhanced Bluetooth (2.0)?
2.1 MHz
170. What is the
typical power rating of most Bluetooth devices?
1mW
171. In the generator,
which one is grounded in order to reduce the radio frequency noise?
armature
172. What is the maximum VF tone that may be fed to a voice signal?
+6 VU
173. In one
atmospheric pressure, what is the velocity of sound in steel?
5150 m/s
174. The electronic
serial number (ESN) assigned at the factory of cellular mobile phone consists
of __________ bits.
32
175. The average
voltage of a 3.58 MHz modulated chrominance signal in TV receivers is
__________.
the brightness
of the color
176. Antennas with micro
strip in PCBs
Patch antenna
177. What is the
wavelength range of sunlight?
300 nm to 2000
nm
178. What is the
peak wavelength of sunlight?
500 nm
179. Radio system
that was developed to provide ng high speed packet data access for GSM network
GPRS
180. A 3G wireless
system can increase its network capacity by ___________ percent as compared to
lower generation wireless system.
70%
181. Sound provides all sorts of information, what information is ralated to mental processes of knowledge, reasoning, memory, judgment and perception?
cognitive
182. What increase
in sound level is commonly perceived by most people?
6 to 10 dB
183. At what
loudness level do pitch (in mels) and frequency (in Hz) are numerically
equal?
40 dB
184. A __________
is essentially a cell site (shelter) that is mounted on a flatbed
tractor-trailer used for emergency purposes
COW
185. This fix tuner
is designed to provide just the exact selectivity required to pass both the IF
signals?
SAW (Surface
Acoustic Wave)
186. Single pulses
that can travel through a medium with no dispersion.
Solitons
187. It is a unique
address for a pager
Capcode
188. Transmission
of brief text message, such as pages or email, by cellular radio or PCS.
Short messaging
service
189. In cellular or
PCS system, connecting a mobile to two or more base stations simultaneously is
called
Soft hand-off
190. It is a number
that identifies a mobile phone in a cellular system; the mobile telephone
number.
Mobile
identification number (MIN)
191. In cellular
phone, a memory location that stores the telephone number(s) to be used on the
system.
Number
assignment module (NAM)
192. In the AMPS
system, a number transmitted by the base station to identify the system
operator.
SID (system
identification number)
193. Code which
describes the maximum power output of a cellular phone
Station Class
Mark (SCM)
194. In a Medium
earth orbit (MEO) satellite, A satellite in orbit at a distance above the
earth’s surface of approximately
8,000 to 20,000
km
195. It is the
change in direction of polarization of signals passing through the ionosphere.
Faraday rotation
196. A metal object threaded into a waveguide to add capacitance or inductance.
Tuning screw
197. In a microwave
tube, any device that cause a wave to propagate at less than the speed of
light, so that the electron beam and the wave move at approximately the same
speed
Slow-wave
structure
198. It is the
method of providing high-speed data transmission on twisted-pair telephone
loops by using high frequency carriers.
Asymmetrical
digital subscriber line (ADSL).
199. In a klystron,
it is a cavity that velocity-modulates the electron beam.
Buncher
200. It is a
circuit for digitizing voice at a low data rate by using knowledge of the way
in which voice sound are produced.
Vocoder
201. It is an
oscillator whose frequency is controlled by a binary number written to an
internal register.
Numerically
controlled oscillator
202. It is a
colloquial term used to describe additional side frequency produced by over
modulation or distortion in an AM system
Splatter
203. A signal
consisting of two audio frequencies not harmonically related, used to test
single sideband transmitters
Two tone test
204. These are now
being used to “sign” important documents that are sent electronically
Digital
signature
205. Cable-television
systems reduce losses by moving UHF signals to the VHF range. They use
frequencies
between channel
6 and 7 and above channel 13
206. It is a
low-level signal in a telephone receiver deriving from the transmitter in the
same instrument. It assures the user that the system is working
sidetone
207. Why is a Smith
chart circular?
Because it is a
convenient way to represent the fact that impedance on a transmission
line repeat every one-half wavelength
208. What characteristic
of solitons makes them interesting for long-distance fiber optic transmission?
Solitons can
propagate for very long distance without dispersion
209. What would be
the most important advantage of converting the entire telephone system,
including local loop, to the fiber optics?
Fiber would
allow almost unlimited bandwidth, enabling one cable to carry all needed
information services to the home
210. What feature
of SONET allows data stream with different clock to be synchronized?
The payload
pointer allows synchronization by indicating the start of a data frame
211. The use of
Solitons and heterodyne reception may allow fiber optics to operate with much
higher data rates and over longer distances without repeaters than any other
system now in use.
212. Why can AM
radio stations often be received at distances beyond the horizon?
Ground waves
follow the curvature of the earth and ground wave can propagation is possible
at AM broadcasting frequencies.
213. Why is antenna
height important for line-of-sight propagation?
Greater antenna
height increases the distance to the radio horizon
214. What is the
main advantage of fiber optics in LANs compared to twisted pair wiring?
Fiber allows for
much longer distances between nodes that can be used with twisted pairs.
215. What is down
tilt and why is it often used for cellular base stations?
Down tilt
involves shifting an antenna pattern so that the major lobe is at an angle
below the horizontal. It can be used to reduce the range of a base station to
reduce interference.
216. What radio
system was developed to provide high speed packet data access for the GSM
channels
GPRS
217. The most
ambitious of the proposed LEO systems.
Teledesic System
218. Why are soft
handoffs not possible with the GSM and TDMA systems?
Because these
systems use different frequency channels in adjacent cells so it is not possible to communicate through more than one
call site at a time
219. Why are
geostationary satellites unsatisfactory for communication from regions near the
poles of the earth?
The angle of
elevation to the satellite is too low to be practical in these regions.
220. It is a
receiver in which that signal is amplified at its original frequency before
demodulation
TRF
(Tuned-radio-receiver)
221. The pulses in
the vertical blanking interval of a video that create interlaced scan.
Equalizing
pulses
222. What connector
is popular in attaching test instruments like oscilloscopes, frequency
counters, spectrum analyzers, etc?
BNC
223. In a klystron,
it is a cavity that removes some of the energy from the electron beam and
transfers it in the form of microwave energy output.
Catcher
224. What connector
is popular in attaching test instruments like oscilloscopes, frequency
counters, spectrum analyzers, etc?
BNC
225. It is the
velocity modulation of a electron beam
Bunching
226. What is
IMT2000 Stands for?
IMT stands for
International Mobile Telecommunications, and 2000 refers both to the
approximate implementation date and to the fact that the proposed system will
operate at about 2000 MHz
227. IMT2000
Maximum data rate for mobile user in high speed vehicles is
144kb/s
228. IMT2000
Maximum data rate for mobile user in for pedestrian or perhaps slow moving
vehicles is
384kbps
229. IMT2000
Maximum data rate for stationary user is
2Mbps
230. It is the only
way to achieved a wider aspect ratio with the current systems is to use fewer
active scan lines
Letterboxing
231. MPEG-2
compression begins by reducing the number of bits required to transmit a
reference frame. This is done using an algorithm called
Discrete cosine
transformation (DCT)
232. What video
standard deals with low data rate video such as are often found in CD-ROMs, and
on the internet?
MPEG1
233. The standard
for terrestrial digital television transmission is called:
8-VSB
234. It is a special cable that consists of two parallel wires with a grounded shield around them. It is sometimes used for gigabit Ethernet.
Twinax cable
235. Ethernet
system that uses a special “thick Ethernet”.
A standard
classical
236. Another
problem with Baudot is that an error that is interpreted as a FIGS character
can cause all the following information to be interpreted as numerical until
the next LTRS character occurs. To reduce this problem, most modern system use
technique called
unshift-on-space
(USOS)
237. Each block of
data is preceded by an eight-bit pattern called a flag, which signals the start
of a frame. In SDLC and HDLC the flag consists of the bit sequence
01111110
238. The IBM
token-ring network uses twisted-pair wiring and can operate at either
__________.
4 Mb/s or 16
MB/s.
239. The IBM
token-ring network could support how many nodes with special data grade shielded
twisted-pair wiring?
260 nodes or 72 nodes using telephone twisted-pair wiring
240. Method of data
compression by encoding the length of string of ones or zeros instead of
transmitting all the one or zero bits individually.
Run-length
coding
241. A data
compression scheme that replaces repeated characters or bit patterns with a
code indicating character or pattern and the number
repetitions
Run-length
coding
242. Loss-less compression
scheme generally looks for redundancies in the data for instance the string of
zeros can be replaced with a code that tells the receivers the length of the
string. What do you call this technique?
Run-length
coding
243. Encryption of
data is important to ensure its privacy. It is most commonly achieved by using
a public-key encryption to transfer a key to be used in __________.
a symmetrical
private key
244. It is the
deviation of a wave as it passes an obstacle that passes through a small
aperture
Diffraction
245. It is a
television receiver design that uses mixing between the picture and sound
carriers to generate the sound intermediate frequency.
Intercarrier
sound
246. A spurious pattern or other distiortion in a facsimile record copy caused by unwanted modulation products arising from the transmission of a carrier signal, and appearing in the form of a rectified baseband that interferes with the lower sideband of the carrier.
Kendall effect
Note: The Kendall effect
occurs principally when the single-sideband width is greater than half of the
facsimile carrier frequency.
247. It is the
interchanging of the frequencies of carrier channels to accomplish specific
purposes, such as to prevent feedback and oscillation, to reduce crosstalk, and
to correct for a high frequency-response slope in the transmission line.
Frequency
Frogging
248. About the Low
earth orbit (LEO) satellite, the first problem is less important than it might
seem. Shorter range results in much less propagation loss and removes the
requirement for highly directional antenna. This makes antenna tracking less
critical. In any case, if the antenna is mounted on a moving vehicle or person
the direction to the satellite is constantly changing. Even with geostationary
satellite. When
real time communication is required, the only way to address the second problem
is to use a __________ containing more than one satellite.
Constellation
249. It is the
cheapest LAN configuration, and if one station fails the whole system fails.
Ring topology
250. A network
station which all station attach to a common cable and the fastest LAN
configuration.
Bus topology
251. Cellular
radios that use FM has a maximum deviation of ___________.
+-12kHz
252. In the GSM
system, a telephone number that is unique to a given user, worldwide
International
Mobile Subscriber Identification (IMSI)
253. A frequency
multiplier can be created by tuning the output circuit of a class C amplifier
to a
multiple of the
input frequency
254. The __________ is a variation on the discriminator. It greatly reduces
sensitivity to amplitude variations, at the cost of a 50% reduction in output
voltage.
radio detector
255. It is the time
between the instant of going off-hook and the instant of receiving a dial tone.
dial-tone delay
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