Term
What reason for modulation involves modulating low frequency signals for transmission over
long distances? |
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Definition
|
|
Term
What are the three general categories used to produce modulation in radio frequency (RF)
transmission today? |
|
Definition
| Amplitude, frequency, and phase |
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Term
When the modulating signal and carrier signal are combined within a modulator, the output
signal contains a/an |
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Definition
| carrier, upper sideband, and lower sideband |
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Term
If a carrier frequency of 1 MHz and a modulating tone of 10 kHz goes to the modulator, the
output signal include |
|
Definition
| 1.01 MHz, 1 MHz, and 0.99 MHz |
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|
Term
If the modulating audio signal is 10 kHz wide, what is the bandwidth of the transmitted
amplitude modulated signal? |
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Definition
|
|
Term
| The bandwidth of an amplitude modulated signal is |
|
Definition
| two times the modulating signal |
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Term
The amount of effect or change that the intelligence has on the carrier in an amplitude
modulated signal is expressed as the |
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Definition
|
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Term
| Which statement concerning bandwidth is true |
|
Definition
| Overmodulating increases bandwidth due to the production of harmonics |
|
|
Term
| Reducing modulation to less than 100 percent gives |
|
Definition
| no reduction in carrier power |
|
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Term
| In frequency modulation (FM), the amount of oscillator frequency change is |
|
Definition
| directly proportional to the amplitude of the modulating signal |
|
|
Term
| In frequency modulation (FM), what is considered a significant sideband? |
|
Definition
| Sidebands containing at least 1 percent of the total transmitted power |
|
|
Term
| What is the formula to find the modulating index? |
|
Definition
| Deviation divided by frequency of modulation |
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Term
| In phase modulation (PM), the carrier’s |
|
Definition
| phase is shifted at the rate of the modulating signal. |
|
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Term
| What is the advantage of adding more phase shifts? |
|
Definition
| Higher data rates within a given bandwidth. |
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|
Term
| What is the first step in the pulse code modulation (PCM) process? |
|
Definition
| The analog signal is band-limited |
|
|
Term
What part of the pulse code modulation (PCM) process converts a continuous time signal
into a discrete time signal? |
|
Definition
|
|
Term
A type of pulse modulation (PM) that changes the amplitude of the pulse train to vary
according to the amplitude of the input signal is called |
|
Definition
| pulse amplitude modulation. |
|
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Term
| If an error should occur, what data transmission is lost in a synchronous transmission? |
|
Definition
|
|
Term
When using vertical redundancy check (VRC), what significance does the amount of ones
have in a data bit pattern? |
|
Definition
|
|
Term
What two error detection methods, when used together, are 98 percent effective in detecting
errors? |
|
Definition
| Vertical redundancy check and longitudinal redundancy check. |
|
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Term
What error detection method adds stacked characters, divides it by 255, and disregards the
answer except for the remainder? |
|
Definition
|
|
Term
What error-correction technique sends a retransmittal request by the receiver to the sender if
it finds an error in a received frame? |
|
Definition
| Automatic retransmit on request. |
|
|
Term
When using forward error control as a method of error correction, where does error
correction take place? |
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Definition
|
|
Term
| What does an optical source do? |
|
Definition
| Converts electrical energy into optical energy |
|
|
Term
Light sources that are applicable to fiber optic waveguide are light-emitting diodes (LED)
and |
|
Definition
| semiconductor laser diodes |
|
|
Term
| What type of light is emitted from a laser? |
|
Definition
|
|
Term
| Laser diode power coupling is measured in which range |
|
Definition
|
|
Term
A device that accepts optical signals from an optical fiber and coverts them into electrical
signals is called an optical |
|
Definition
|
|
Term
| Small current that flows from a photodiode even with no light is called |
|
Definition
|
|
Term
| The responsivity of a photo detector is dependent on the |
|
Definition
|
|
Term
| What are the two main types of photodetectors? |
|
Definition
| Positive intrinsic negative and avalanche photodiode |
|
|
Term
| What photo detector converts one photon to one electron? |
|
Definition
| Positive intrinsic negative (PIN) diode. |
|
|
Term
| What is used to extend the distance of a fiber optic communication systems link? |
|
Definition
|
|
Term
Which repeater amplifies optical signal without converting to and from the electrical
domain? |
|
Definition
|
|
Term
| Short sections of single fiber cables that has a connector at each end is called a |
|
Definition
|
|
Term
Which fiber-optic connector uses quick-release, keyed bayonet couplings that are preferred
in situations where severe vibrations are not expected? |
|
Definition
|
|
Term
| Which fiber optic connector uses a push-pull engagement for mating? |
|
Definition
|
|
Term
| What initial nuclear radiation elements generate electromagnetic pulses? |
|
Definition
|
|
Term
) High-altitude electromagnetic pulse is what type of frequency phenomenon, and involves
which frequency range? |
|
Definition
| Wideband; 1 hertz to 1 gigahertz |
|
|
Term
A system-generated electromagnetic pulse is a problem for satellites and reentry vehicles
that are |
|
Definition
| directly exposed to nuclear radiations from a high-altitude burst |
|
|
Term
Which distinct region of the source region electromagnetic pulse is produced by the
interactions between the weapon products and the earth’s atmosphere? |
|
Definition
|
|
Term
| What electromagnetic pulse region is the principal threat to electronic systems by cable? |
|
Definition
|
|
Term
| How does scintillation effects communications? |
|
Definition
Transmitted signal fading caused by multiple path propagation through the structured plasma
field. |
|
|
Term
Atmospheric disturbances from initial nuclear radiation on higher frequencies affect
communications by which types of effects? |
|
Definition
|
|
Term
| Which one of the following statements are true concerning shielding? |
|
Definition
| Sensitive equipment will be located within the shielded barrier |
|
|
Term
| What is the purpose of bonding? |
|
Definition
| To ensure a mechanically strong, low impedance interconnection between metal objects |
|
|
Term
| Which types of filters are always used in combination with surge arresters? |
|
Definition
|
|
Term
If the interference can be eliminated by disconnecting the receiving antenna, the source of
the disturbance is most likely |
|
Definition
|
|
Term
| What is an example of intentionally induced electromagnetic interference (EMI)? |
|
Definition
|
|
Term
| What type of electromagnetic interference (EMI) occurs when a receiver responds to off frequency signals? |
|
Definition
|
|
Term
| What type of equipment often generates many spurious emissions? |
|
Definition
| Rapid tuning transmitter. |
|
|
Term
| What man-made noise results from voltage surges, arcing, or corona discharges? |
|
Definition
|
|
Term
How can you normally eliminate electromagnetic interference (EMI) noise bursts caused by
sodium and mercury vapor lights that have stopped working while the power is still applied? |
|
Definition
|
|
Term
| What Air Force program is used to resolve an electromagnetic interference (EMI) incident? |
|
Definition
| Spectrum interference resolution (SIR). |
|
|
Term
At what level does the Air Force want electromagnetic interference (EMI) problems
resolved? |
|
Definition
|
|
Term
| What is the first step in the Air Force spectrum interference resolution (SIR) program? |
|
Definition
|
|
Term
| What do you do when you are reasonably sure electromagnetic interference (EMI) exists? |
|
Definition
| Systematically gather data for analysis |
|
|
Term
| Who is initially responsible for reporting an electromagnetic interference (EMI)? |
|
Definition
|
|
Term
| Which Air Force service provides on-site direction finding and interference problem |
|
Definition
| Quick Fix Interference Reduction Capability |
|
|
Term
| What program addresses persistent and recurring interferences problems in joint operations? |
|
Definition
| Joint Spectrum Interference Resolution (SIR). |
|
|
Term
| Who is tasked to provide interference resolution support to the unified commanders? |
|
Definition
| Joint Spectrum Center (JSC). |
|
|
Term
Which feature of the Fluke 8025A locks the measurement into the display for viewing and
automatically updates the display when you take a new measurement? |
|
Definition
|
|
Term
Which current range on the Fluke 8025A do you select to measure 250 milliamps
alternating current (AC)? |
|
Definition
|
|
Term
When testing a diode with the 8025A, the leads across a “good” diode produces an “OL”
(open) on the display in one direction while reversing the leads produces |
|
Definition
| a continuous audible tone |
|
|
Term
| How are voltage, time, and depth represented on the oscilloscope display? |
|
Definition
| Voltage = vertical axis, time = horizontal axis, and depth = intensity. |
|
|
Term
Which mode of triggering an oscilloscope causes a trace to be drawn on the screen at all
times, whether there is an input signal or not? |
|
Definition
|
|
Term
| Which probe does not need to actually make contact with the circuit under test? |
|
Definition
|
|
Term
What digital storage oscilloscope circuit compensates for high sampling rates of high
frequency signals? |
|
Definition
|
|
Term
| Sampled data points are stored in the memory of a digital storage oscilloscope as |
|
Definition
|
|
Term
What area of a digital storage oscilloscope takes digitized samples and performs numerous
manipulations on the data including measuring rise and fall times, periods, time intervals, and
math computations? |
|
Definition
|
|
Term
What type of sampling does a digital storage oscilloscope normally use on single-shot or
seldom-occurring signals? |
|
Definition
|
|
Term
| In real-time sampling, what type of interpolation is used when measuring pulse waves? |
|
Definition
|
|
Term
) Which are the three types of digital storage oscilloscope acquisition modes, and which is the
standard operating mode? |
|
Definition
| Sample, peak detect, averaging; sample. |
|
|
Term
) In acquiring a 4K record length on a digital storage oscilloscope, how many samples can
you view at one time? |
|
Definition
|
|
Term
What test equipment provides a bit error detection system that can determine the received
data quality after traveling over a communications link? |
|
Definition
|
|
Term
What pattern simulator section of the bit error rate test set accepts a 48-bit parallel word and
generates a serial pattern? |
|
Definition
|
|
Term
What pattern simulator section of the bit error rate test set converts the non-return zero-level
(NRZ-L) data into the desired coding, such as non-return zero-mark (NRZ-M)? |
|
Definition
|
|
Term
What pattern synchronizer and error counter section of the bit error rate test set internally
generates its own pattern to compare with the received data from the data/clock receivers? |
|
Definition
| Pseudo random noise (PRN) synchronizer/comparator. |
|
|
Term
| Which of these bit rates do you use for a bit error rate test on a 64 Kbps data circuit? |
|
Definition
|
|
Term
On the bit error rate test (BER) set, the 25-pin connectors are designed to operate with data
modems to |
|
Definition
| simplify connection of test equipment to the modem under test and to carry the necessary |
|
|
Term
| System grounds must continually be tested |
|
Definition
|
|
Term
A known current is generated by the earth ground tester between the earth ground electrode
and the |
|
Definition
|
|
Term
| Where is voltage potential measured in the fall of potential ground testing method? |
|
Definition
| Between the auxiliary potential electrode and the earth ground electrode |
|
|
Term
The Institute of Electrical and Electronics Engineers (IEEE) have recommended a ground
resistance value of |
|
Definition
|
|
Term
What component on a protocol analyzer process the frames based on the selected test and
user configuration inputs? |
|
Definition
| Central processing unit (CPU). |
|
|
Term
What protocol analyzer test window provides information concerning the network
utilization and frame error that are related to a specific protocol? |
|
Definition
|
|
Term
What protocol analyzer test window reports errors that occur at the physical layer such as
bad frame check sequence (FCS), short frames, and jabbers? |
|
Definition
| Media access control (MAC) node statistics |
|
|
Term
What active test is selected to see the path that the packets are traveling and the time it takes
the packets to compete the trip |
|
Definition
|
|
Term
| Which one of these is not an application of a radio frequency (RF) generator? |
|
Definition
| Verifying transmitter frequencies |
|
|
Term
| A power reading that uses the abbreviation dBm indicates the |
|
Definition
| ratio of decibels relative to a 1-milliwatt standard |
|
|
Term
During what operation is the radio frequency blanking output used on the HP 436A power
meter? |
|
Definition
| During the automatic zeroing operation |
|
|
Term
| Plug-in elements of the wattmeter are selected based on the |
|
Definition
| frequency and power to be measured |
|
|
Term
| The two switches on the front panel of the wattmeter is to correspond to the |
|
Definition
| power range of the forward element |
|
|
Term
| When reading forward power on a wattmeter, what does two right facing arrow head mean? |
|
Definition
| Power exceeds 120 percent of the range. |
|
|
Term
) What feature is useful for making adjustments to optimize any of the parameters which the
wattmeter measures? |
|
Definition
|
|
Term
| Which measurements are not made with a spectrum analyzer? |
|
Definition
|
|
Term
| Which are the correct four classes of electronic counters? |
|
Definition
| Frequency counters, universal counters, microwave counters, and reciprocal counters. |
|
|
Term
What test equipment combines the operations of many test instruments into a single
compact unit? |
|
Definition
| Communication service monitor |
|
|
Term
| What function is not part of the communication service monitor? |
|
Definition
|
|
Term
What operational capability of the communication service monitor produces sine, square,
and triangle waveforms? |
|
Definition
|
|
