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3C231 - Block II
Telecomunications Fundamentals
63
Computer Science
Professional
12/08/2008

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Cards

Term
A component consisting of two conducting surfaces (plates) seperated by an insulator.
Definition
A Capacitor
Term
What are the two types of capacitors?
Definition
Fixed and variable
Term
The measure of a capacitor's ability to store energy in the form of an electrostatic field
Definition
Capacitance
Term
The symbol for capacitance is ____ and is measured in _________.
Definition
C and measured in Farads
Term
When placing capacitors in series, what is the formula to find total capacitance?
Definition

C=             1            

                      1_   1_   1_

                     C1         C2      C3

Term
When placing capacitors in parallel, what is the formula to find total capacitance?
Definition
Ct = C1 + C2 + C3...
Term

What is the formula for capacitive reactance (XC)?

Definition

         Xc__1__  or   _0.159__

                  2∏fC               fC

Term

What is the formula for inductance?

Definition

L  =  N2

       l

Term
When placing indicators in series, what is the formula for total inductance?
Definition
LT  =  L1 + L2 + L3 ...
Term
When placing indicators in parallel, what is the formula for total inductance?
Definition

              LT =  _______1________

                              _1_    1_ + _1_ ....

                               L1         L2        L3

Term
What are the formulas for time and frequency?
Definition
t = 1/f    f = 1/t
Term
What are the two formulas for calculating wavelength?
Definition
λ = v/f   and vt
Term
What is the formula for inductive reactance?
Definition
XL = 2∏fL   or   6.28fL
Term
What is the formula for effective voltage?
Definition
Eeff = .707 x Epk
Term
What is a device designed to control current flow through a circuit?
Definition
Resistor
Term
What do we call the movement of electrons from atom to atom?
Definition
Current
Term
The chemical reaction that causes the atoms on the positive side of a battery to lose electons, while the negative side gains electrons is called what?
Definition
Ionization
Term
What kind of current flows in only one direction?
Definition
Direct Curent  (DC)
Term
What are 4 requirements for a basic circuit?
Definition
  1. Voltage Source
  2. Conductor
  3. Continuity
  4. Load Source
Term
What type of circuit provides only one path of current flow?
Definition
Series Circuit
Term
What is the electrical energy that causes electrons to move through a circuit?
Definition
Voltage
Term
Ohm's Law part 2 of 2 states that current is __________ proportional to resistance?
Definition
Inversely
Term
What effect do insulators have on current flow?
Definition
The inhibit current flow
Term
Ohm's Law part 1 of 2 states current is _____________ proportional to voltage.
Definition
Directly
Term
What do you call electrons in the outermost orbit of an atom?
Definition
Valence
Term
What kind of resistor is the most common type of fixed resistor and used in low current applications?
Definition
Carbon Resistor
Term
What is the most common type of AC waveform, representing voltage and current?
Definition
Sine Wave
Term
What's the difference between a series and a parallel circuit?
Definition
A Series has only one path and a Parallel has two paths
Term
At what point in a sinewave cycle is it possible to measure the peak voltage?
Definition
At the peak of the alternation
Term
After a sine wave has gone through one cycle, it repeats itself to form a ___________.
Definition
Wave Train
Term
What is a graphic representation of how voltage and current changes in amplitude and direction?
Definition
Sine Wave
Term
Frequency and the time of a sine wave are _________ proportional.
Definition
Inversely
Term
What happens to the wavelength if the time of one cycle increases?
Definition
It increases
Term
What happens to wavelength if frequency increases?
Definition
It decreases
Term
What 3 conditions must exist for sine waves to be considered in-phase?
Definition
  1. Must be of the same frequency
  2. Reach peaks at the same time
  3. Pass zero axis at the same time
Term

In a capacitor, what phase relationship exists between current and voltage?

Definition
Current leads voltage
Term
What is the opposition that a capacitor offers to AC current flow?
Definition
Capacitive reactance
Term
If frequency goes up, what happens to capative reactance?
Definition
Decreases
Term

What is the symbol for inductance?

Definition
L
Term
What is the unit of measure for inductance?
Definition

(H) Henry

Term
What happens to inductive reactance if Frequency (f) increases?
Definition

It will increase

Term
What is the frequency that causes XC and XL to become equal?
Definition
The Resonant Frequency
Term

Which type of signal format alternates the voltage polarity between successive mark bits?

Definition
AMI
Term

How does quasi-analog signal format differ from the other signal formats?

Definition
Its an analog signal with digital information
Term
What is the formula for upper sideband?
Definition
fc+fm
Term
What are the 2 types of detection for PSK?
Definition
Fixed Reference and Differential
Term
Which PSK process uses 2 input data bits to make an output decision?
Definition

QPSK

Term

Which modulation technique must you use for data rates over 35 Mb/S?

Definition
QAM
Term
What distortion is created by the delta modulation process?
Definition
Slope Overload Distortion
Term
How does CVSD differ from DM?
Definition
It has non uniform steps
Term
What states that for a signal to be reproduced accurately, it must be sampled at twice the highest frequency?
Definition
Nyquist Theorom
Term
What is the sample rate for a voice signal?
Definition
8000 times per second or 0-4kHz
Term
What logarithmic scale has 16 chords and 16 steps with each chord?
Definition
Mu-Law 255
Term
What is the sample rate of ADPCM?
Definition
4 Bit word per sample
Term
What do the 2nd, 3rd, and 4th bits represent in a PCM word?
Definition
The highest chord in the PAM sample achieved in the quantizer
Term
What do the last four bits of a PCM word represent?
Definition
The step to which the sample was rounded
Term
Where is the Conditioned diphase interface (CDI) technique predominately used? 
Definition
Tactical Environment
Term
What is the part of the signal that occupies the shortest interval of a signaling code?
Definition
Unit Interval
Term
What is the amount of time a digital signal is left at a particular voltage to indicate a value?
Definition
Bit Interval
Term
What is counting the number of bits recieved in a specific time interval (usually one second)?
Definition
Bit Count Integrity
Term
What is the measurement of the signaling speed of a data transmission device?
Definition
Baud Rate
Term
What is  the term that describes when a carrier is at a frequency other than the center frequency?
Definition
Deviation
Term

What happens to wavelength if frequency increases?

Definition
Gets shorter
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