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1993-03-09
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128D-5.1 B 4-13 PEP = [(0.707 PEV)(0.707 PEV)] / RL
How can the output PEP of a transmitter be determined with an
oscilloscope?
A. Measure peak load voltage across a resistive load with an
oscilloscope, and calculate, using PEP = [(Vp)(Vp)] / (RL)
B. Measure peak load voltage across a resistive load with an
oscilloscope, and calculate, using
PEP = [(0.707 PEV)(0.707 PEV)] / RL
C. Measure peak load voltage across a resistive load with an
oscilloscope, and calculate, using PEP = (Vp)(Vp)(RL)
D. Measure peak load voltage across a resistive load with an
oscilloscope, and calculate, using
PEP = [(1.414 PEV)(1.414 PEV)] / RL
*
129D-5.5 A 4-13 PEV = .5*Vpp, PEV = 100|Vrms = .707*PEV, Vrms = 70.7|P = Vrms*Vrms/R, P = 5000/50
What is the output PEP from a transmitter when an oscilloscope
shows 200-volts peak-to-peak across a 50 ohm resistor connected
to the transmitter output terminals?
A. 100 watts
B. 200 watts
C. 400 watts
D. 1000 watts
*
130D-5.6 B 4-13 PEV = .5*Vpp, PEV = 250|Vrms = .707*PEV, Vrms = 176.8|P = Vrms*Vrms/R, P = 31240/50
What is the output PEP from a transmitter when an oscilloscope
shows 500-volts peak-to-peak across a 50 ohm resistor connected
to the transmitter output terminals?
A. 500 watts
B. 625 watts
C. 1250 watts
D. 2500 watts
*
131D-5.7 B 4-13 For a CW signal(unmodulated)|PEP and Average are the same|power level
What is the output PEP of an unmodulated carrier transmitter
when an average-reading wattmeter connected to the transmitter
output terminals indicates 1060 watts?
A. 530 watts
B. 1060 watts
C. 1500 watts
D. 2120 watts
*
132D-6.1 D 4-7 Oscilloscope
What item of test equipment contains horizontal and vertical
channel amplifiers?
A. The ohmmeter
B. The signal generator
C. The ammeter
D. The oscilloscope
*
133D-6.2 A 4-7 Signals within the bandwith|capability of the equipment
What types of signals can an oscilloscope measure?
A. Any time-dependent signal within the bandwidth
capability of the instrument
B. Blinker-light signals from ocean-going vessels
C. International nautical flag signals
D. Signals created by aeronautical flares
*
134D-6.3 D 4-6 A piece of equipment that|displays signal waveforms
What is an oscilloscope?
A. An instrument that displays the radiation resistance of
an antenna
B. An instrument that displays the SWR on a feed line
C. An instrument that displays the resistance in a circuit
D. An instrument that displays signal waveforms
*
135D-6.4 B 4-8 Too much brightness
What can cause phosphor damage to an oscilloscope cathode
ray tube?
A. Directly connecting deflection electrodes to the cathode
ray tube
B. Too high an intensity setting
C. Overdriving the vertical amplifier
D. Improperly adjusted focus
*
136D-9.1 C 4-8 A piece of test equipment that|detects signals in a circuit
What is a signal tracer?
A. A direction-finding antenna
B. An aid for following schematic diagrams
C. A device for detecting signals in a circuit
D. A device for drawing signal waveforms
*
137D-9.2 A 4-8 A signal tracer is used to detect|the presence of a signal
How is a signal tracer used?
A. To detect the presence of a signal in the various stages
of a receiver
B. To locate a source of interference
C. To trace the path of a radio signal through the ionosphere
D. To draw a waveform on paper
*
138D-9.3 D 4-8 A signal tracer is used to identify|an inoperative stage
What is a signal tracer normally used for?
A. To identify the source of radio transmissions
B. To make exact replicas of signals
C. To give a visual indication of standing waves on open-
wire feed lines
D. To identify an inoperative stage in a radio receiver
*
139D-10.1 B 4-17 Bypass capacitors
What is the most effective way to reduce or eliminate audio
frequency interference to home entertainment systems?
A. Install bypass inductors
B. Install bypass capacitors
C. Install metal oxide varistors
D. Install bypass resistors
*
140D-10.2 B 4-18 Contact the telephone company|about installing RFI filters
What should be done when a properly operating amateur station
is the source of interference to a nearby telephone?
A. Make internal adjustments to the telephone equipment
B. Contact a phone service representative about installing RFI
filters
C. Nothing can be done to cure the interference
D. Ground and shield the local telephone distribution amplifier
*
141D-10.3 C 4-17 Radio interference to a PA system for|CW would be on-and-off clicking, SSB-|distorted speech, & AM-audible speech
What sound is heard from a public address system when audio
rectification occurs in response to a nearby single-sideband
phone transmission?
A. A steady hum that persists while the transmitter's carrier
is on the air
B. On-and-off humming or clicking
C. Distorted speech from the transmitter's signals
D. Clearly audible speech from the transmitter's signals
*
142D-10.4 C 4-18 Proper grounding of all equipment
How can the possibility of audio rectification occurring be
minimized?
A. By using a solid state transmitter
B. By using CW emission only
C. By ensuring all station equipment is properly grounded
D. By using AM emission only
*
143D-10.5 A 4-17 Radio interference to a PA system for|CW would be on-and-off clicking, SSB-|distorted speech, & AM-audible speech
What sound is heard from a public address system when audio
rectification occurs in response to a nearby double-sideband
phone transmission?
A. Audible, possibly distorted speech from the transmitter
signals
B. On-and-off humming or clicking
C. Muffled, distorted speech from the transmitter's signals
D. Extremely loud, severely distorted speech from the
transmitter's signals
*
144D-12.2 D 4-15 A properly adjusted speech processor|improves intelligibility during poor|conditions
What is the reason for using a speech processor with a single-
sideband phone transmitter?
A. A properly adjusted speech processor reduces average
transmitter power requirements
B. A properly adjusted speech processor reduces unwanted
noise pickup from the microphone
C. A properly adjusted speech processor improves voice
frequency fidelity
D. A properly adjusted speech processor improves signal
intelligibility at the receiver
*
145D-12.3 B 4-16 Max is Max
When a transmitter is 100% modulated, will a speech processor
increase the output PEP?
A. Yes
B. No
C. It will decrease the transmitter's peak power output
D. It will decrease the transmitter's average power
output
*
146D-12.4 C 4-15 A speech processor degrades the signal|quality, thus should not be used when |the frequency in use is clear
Under which band conditions should a speech processor
not be used?
A. When there is high atmospheric noise on the band
B. When the band is crowded
C. When the frequency in use is clear
D. When the sunspot count is relatively high
*
147D-12.5 D 4-15 Improves intelligibility during poor|conditions but slightly degrades the|signal quality
What effect can result from using a speech processor with
a single-sideband phone transmitter?
A. A properly adjusted speech processor reduces average
transmitter power requirements
B. A properly adjusted speech processor reduces unwanted
noise pickup from the microphone
C. A properly adjusted speech processor improves voice
frequency fidelity
D. A properly adjusted speech processor improves signal
intelligibility at the receiver
*
148D-13.1 A 4-14 This device might generate some |harmonics, so it is best between|the transmitter and low-pass filter
At what point in a coaxial line should an electronic T-R
switch be installed?
A. Between the transmitter and low-pass filter
B. Between the low-pass filter and antenna
C. At the antenna feed point
D. Right after the low-pass filter
*
149D-13.2 C 4-15 Faster and less likely to wear out
Why is an electronic T-R switch preferable to a mechanical
one?
A. Greater receiver sensitivity
B. Circuit simplicity
C. Higher operating speed
D. Cleaner output signals
*
150D-13.3 D 4-15 An electronic TR switch is faster|than a mechanical one
What station accessory facilitates QSK operation?
A. Oscilloscope
B. Audio CW filter
C. Antenna relay
D. Electronic TR switch
*
151D-14.6 B 4-16 An antenna noise bridge is used for |measuring the impedance of an antenna|or other electrical circuit
What is an antenna noise bridge?
A. An instrument for measuring the noise figure of
an antenna or other electrical circuit
B. An instrument for measuring the impedance of an
antenna or other electrical circuit
C. An instrument for measuring solar flux
D. An instrument for tuning out noise in a receiver
*
152D-14.7 C 4-16 An antenna noise bridge is tuned for|minimum noise in a receiver at the |desired operating frequency
How is an antenna noise bridge used?
A. It is connected at the antenna feed point, and the
noise is read directly
B. It is connected between a transmitter and an antenna
and tuned for minimum SWR
C. It is connected between a receiver and an unknown
impedance and tuned for minimum noise
D. It is connected between an antenna and a Transmatch
and adjusted for minimum SWR
*
153D-15.1 B 4-10 The top half of the display will look |like the input waveform and the bottom|looks like a mirror image of the top
How does the emitted waveform from a properly adjusted single-
sideband phone transmitter appear on a monitoring oscilloscope?
A. A vertical line
B. A waveform that mirrors the input waveform
C. A square wave
D. Two loops at right angles
*
154D-15.2 A 4-9 Oscilloscope
What is the best instrument for checking the transmitted signal
quality from a CW or single-sideband phone transmitter?
A. A monitor oscilloscope
B. A field strength meter
C. A sidetone monitor
D. A diode probe and an audio amplifier
*
155D-15.3 B 4-8 A monitoring oscilloscope displays the|waveform of the transmitted signal
What is a monitoring oscilloscope?
A. A device used by the FCC to detect out-of-band signals
B. A device used to observe the waveform of a transmitted
signal
C. A device used to display SSTV signals
D. A device used to display signals in a receiver IF stage
*
156D-15.4 D 4-8 Through a coupling device, connect the|transmitter output to the vertical- |deflection plates
How is a monitoring oscilloscope connected in a station in order to
check the quality of the transmitted signal?
A. Connect the receiver IF output to the vertical-deflection plates
of the oscilloscope
B. Connect the transmitter audio input to the oscilloscope vertical
input
C. Connect a receiving antenna directly to the oscilloscope
vertical input
D. Connect the transmitter output to the vertical-deflection plates
of the oscilloscope
*
157D-17.2 A 4-14 A field strength meter
What is the most appropriate instrument to use when determining
antenna horizontal radiation patterns?
A. A field strength meter
B. A grid-dip meter
C. A wave meter
D. A vacuum-tube voltmeter
*
158D-17.3 C 4-14 An RF meter with an antenna used for|monitoring relative RF output of an |antenna, transmitter, etc.
What is a field-strength meter?
A. A device for determining the standing-wave ratio on
a transmission line
B. A device for checking modulation on the output of a
transmitter
C. A device for monitoring relative RF output
D. A device for increasing the average transmitter output
*
159D-17.4 A 4-14 A field-strength meter is an RF meter|with an antenna used for monitoring|relative RF output during testing
What is a simple instrument that can be useful for monitoring
relative RF output during antenna and transmitter adjustments?
A. A field-strength meter
B. An antenna noise bridge
C. A multimeter
D. A Transmatch
*