EST Terms and Definitions Part2


1.    Extended superframe – 576 channels
2.    Delta Modulation – slope overload is common problem
3.    T1 – most common carrier line for telephones
4.    100 dB - RF and IF gain in receiver
5.    0.9 – velocity factor for open wire
6.    0.8 – velocity factor for twin lead
7.    Critical frequency of F2 – 8 MHz
8.    Ephemeris – location of a celestial body in space
9.    troposcatter – 350 MHz to 10 GHz
10.  End impedance of HW dipole – 2500Ω
11.  single hop night time range of F2 – 4130 km
12.  3300 m/s – speed of sound in wood
13.  GSM/TDMA – cannot execute soft handoff because cellsites use different sets of frequencies to communicate with each other
14.  20 phons – typical loudness level of ticking watch
15.  M88 – 88 mH coil; every 9000 feet
16.  Hybrid Transformer – 2 wire to 4 wire converter
17.  click – square wave; rounding off something
18.  SDMA – Spatial Div. Multi Access; use same frequency in multiple focused beams aim at different areas
19.  IS 95 – became CDMA 2000
20.  International pitch A – 435 Hz
21.  Hash – 128 bits sequence in digital signature
22.  Envelope Delay Distortion – caused by freq. dependent attenuation chars of transmission lines
23.   POP3 – Post Office Protocol version 3
24.  Why use geosynchronous satellites? To simplify tracking requirements
25.  BISYNC – not a bit oriented protocol
26.  flag filed for SDLC/HDC – 7Eh
27.  Bit stuffing – to prevent accidental flag fields?
28.  Blank and Burst – interrupt voice feed to send control signals (cellular telephony)
29.  fiber optics are preferred to satellites for long distance telephone transmission because of less delay
30.  real time of info – found in circuit switching
31.  mechanical splicing
32.  fusion splicing – the ends are melted together
33.   2 mV – TV video signal level
34.  for CATV : (noise free picture)
a.     1 mV for 75Ω
b.    2 mV for 300Ω
35.  Synchronous demodulation – process of getting the info from the chroma signal
36.  CW Doppler Radar – used by police
37.  CTCS – Continuous Tone Control Squelch; low frequency tones only
38.  EO 196 – control of PHILCOM SAT to NTC
39.   P 5000 – fine for no permit (MPDP)
40.  P 5000 – per unit fine of unauthorized cellphone service
41.  P 100 K – paid up capital
42.  P 1200 – permit for MPD
43.  P 300- license for CATV head end
44.  Differential Peak Detector – has a peak detector
45.  Sun Detector – orientation of sunlight
46.  Blooming – trapped gas pockets in fiber cables
47.  Service numbers – 3 digit number with specialized service
48.  smart card – card with embedded IC
49.  armature – part of dc radio gen which is grounded to reduce radio noise
50.  MPEG4 - current video compression standard
51.  6 to 10 dB – noticeable change in loudness level
52.  noise figure: (with equalizer)
a.     330 MHz – 9.5 dB
b.    54 MHz – 7.5 dB
53.  12 dB – visual signal level for channels that have other than 6MHz nominal separation
54.  3 dB – visual signal level for channels that have 6MHz nominal separation
55.  13 to 17 dB – sound carrier lower than visual carrier
56.  Cross Luminance – diagonal patterns
57.  S unit – 6 dB
58.  MPDP – apply at NTC regional office of area to service
59.  24.3 kBaud/sec – modulation rate for D-AMPS
60.  150 µV – receiver preampt input (CATV)
61.  SSB – 200 Hz shift results in material degradation
62.  +- 25V – max voltage to apply (data)
63.  GMDSS – Global Maritime Distress and Safety System
64.  AMPS – 10 kbps
65.  Positive Carrier Shift – insufficient grid mod at grid modulation ckt
66.  Negative Carrier Shift – insufficient grid mod at high power modulation
67.  100 milliroentgents/week exposure
68.  0.5 milliroentgents per hour from 5 cm
69.  camera pickup tube – yellow green is most sensitive
70.  wan topologies:
a.     leased line
b.    circuit switching
c.     packet switching
71.  <5% - interference to visual signal level
72.  Measuring rad exposure – device should have area max 10cm2 max linear dimension is 5cm
73.  3 channels – separation between geographically adjacent stations to minimize interference
74.  downtilt – limit range
75.  GPS – uses CDMA for multiple access tech
76.  1800 Hz – reference frequency for envelope delay distortion measurement
77.  Two tone test – SSB method in testing AM transmitter
78.  Pump laser – to higher energy level
79.  MPEG2 – Discrete Cosine Transform
80.  IMTS – Improved Mobile Tel System; Bell Labs, 1965 or 68
81.  PON – not needing to install expensive equipment at every terminal
82.  Ethernet – uses 3 level Manchester code
83.  CT 2 – portable payphone booth
84.  SSB  - assigned frequency is 1.4 kHz above carrier frequency
85.  Linear amplifier – frequency instability for J3E because there’s no carrier reference
Horn and slot – direct connection to waveguides

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