Transcript Serious ‘XM (That’s W2XM) presents

Serious ‘XM
(That’s W2XM)
presents
Exam-prep Jepperdee:
Extra-class Edition, v. 2
To prepare for the 2012 edition of the Extra exam
Announcements:
Introduction of presenter:
Operation of the game is almost intuitive, and you can make up
your own rules. Each numeric point value on either game board is a
hyperlink which reveals a question. Advancing the game one slide
past the question (by clicking the screen) displays the answer. “Back”
on the answer slide returns you to the game board. “SFJ” stands for
“semi-final jepperdee” and “FJ” means “final jepperdee;” proceed
from SFJ or FJ by clicking the screen until you see the next hyperlink.
There is one daily double on each board; click exactly on “Daily” or
“Double” to see the question.
For most fun, appropriate hardware (lights, push-buttons,
sounder, lockout circuitry) should be used. A diagram is found at the
end of this slide show.
OPERATING
PRACTICES
RULES AND
REGULATIONS
ELECTRICAL
PRINCIPALS
COMPONENTS &
BLDG BLOCKS
100
100
100
100
200
200
200
200
300
300
300
300
400
400
400
400
500
500
500
500
SFJ
Electronic
Circuits
Radio Sigs. Modes & Antennas/
& Msrmnts Equipment Propagation
100
100
100
100
200
200
200
200
300
300
300
300
400
400
400
400
500
500
500
500
FJ
Which data are
used by the APRS
network to
communicate your
location?
E2D11
Latitude and
longitude
back
Which of the
following types of
packet frames is
used to transmit
APRS beacon data?
E2D08
Unnumbered
Information
back
What type of
satellite appears to
stay in one position
in the sky?
E2A13
Geostationary
back
What is the
orbital period of
an Earth satellite?
E2A03
the time it takes for
the satellite to complete one rev. around
the Earth; this
depends on altitude
back
What is “selfspotting” in regards
to contest
operating?
E2C02
The practice of
posting one’s own
call sign and freq.
on a call sign spotting network
back
Is it legal to make a
call using USB while
your transceiver is
displaying a “carrier”
frequency of 14.349
MHz?
E1A03
No; the sideband
will extend beyond
the band edge.
back
Within what
distance must an
amateur station protect an FCC monitoring facility from
harmful interference?
E1B03
1 mile
back
How are the control
op responsibilities
different for a station
under automatic
control and for one
under local control?
E1C03
Under automatic
control, the control
op is not required to
be present at the
control point
back
What is a
telecommand station
in the amateur
satellite service?
E1D03
An amateur station
that sends signals
to initiate, modify
or end functions of
a space station
back
What is a
Volunteer
Examiner
Coordinator?
E1E03
An organization that
has entered into an
agreement with FCC
to coordinate license
exams
back
What are the
differences between
the radiation from
radioactive materials
and the EM energy
from an antenna?
E0A01
Radioactive stuff
emits ionizing
radiation; RF signals
are weaker and can
only cause heating
back
What do the two
numbers represent that
are used to define a
point on a graph using
rectangular
coordinates?
E5C11
The coordinate
values along the
horizontal and
vertical axes
back
What characteristic of a series-tuned
circuit can be used as
a relative indicator of
its Q?
E4B15
The bandwidth of
the circuit's
frequency
response
back
What is the resonant freq. of a series
RLC circuit if R is 56
ohms, L is 40
microhenrys and C is
200 pf?
E5A15
1.78 MHz
back
Which point in the
next slide represents the
impedance of a series
circuit consisting of a 300
ohm resistor and an 18
microhenry inductor at
3.505 MHz?
E5C20
Point 3
Point 2
Point 8
Point 5
Point 6
Point 4
Point 7
Point 1
Point 3
back
What’s the name
given to an impurity
atom that adds holes
to a semiconductor
crystal structure?
E6A04
Acceptor impurity
back
What is one
common use for
PIN diodes?
E6B12
As an RF switch
back
What is the main
advantage of liquidcrystal display (LCD)
devices over other
types?
E6D15
They consume less
power.
back
What is an
advantage of a
period-measuring
freq. counter over a
direct-count type?
E7F11
It gives improved
resolution of lowfreq. signals within
a comparable time
period.
back
What is the
approx. open-circuit
voltage produced by
a fully-illuminated
Si photovoltaic cell?
E6F11
0.5 volts
back
How can an
RF power
amplifier be
neutralized?
E7B08
By feeding a 180degree out-ofphase portion of
the output back to
the input
back
How does one insure that a xtal oscillator provides the
frequency specified
by the crystal mfr?
E6E09
Provide the crystal
with the specified
parallel capacitance
back
What condition
must exist for a
circuit to
oscillate?
E7H02
It must have
positive feedback
with a gain greater
than 1
back
Why is Pi-L network better than a Pi
for z matching btwn a
vacuum-tube PA and
the antenna?
E7C03
Greater harmonic
suppression
back
What is the
purpose of C1 in
the circuit shown in
the next slide
(Figure E7-3)?
E7D09
Figure E7- 3
Q1
+25
C1
4000
C2
4000
+12
C3
0.01
R1
D1
R2
It filters the supply
voltage.
back
What is the
period of a wave?
E8A08
The time required
to complete one
cycle
back
What is the RMS
value of a 340-volt
peak-to-peak pure
sine wave?
E8D16
120 V
back
Which of these
factors most affects
the accuracy of a
frequency counter?
E4B01
(next slide)
A) Input attenuator
accuracy; B) Time base
accuracy; C) Decade
divider accuracy;
D) Temperature
coefficient of logic
Time base
accuracy
back
What is one use
for a pulse
modulated signal?
E8A11
Digital data
transmission
back
What is one type of
elec. interference that
might be caused by
the operation of a
personal computer?
E4E14
The appearance of
unstable modulated
or unmodulated
signals at specific
frequencies
back
Why are
received spreadspectrum signals
resistant to
interference?
E2C08
Signals not using
the spectrumspreading algorithm
are suppressed in
the receiver
back
Which of these
techniques causes a
digital signal to appear
as wide-band noise to
a conventional rcvr?
E8C09
(next slide)
A)
B)
C)
D)
Spread-spectrum
Independent s.b.
Regenerative det.
Exponential addition
Spread-spectrum
back
How many
times/sec is a new
frame transmitted
in a fast-scan
(NTSC) t.v. system?
E2B01
30
back
What is an effect
of excessive phase
noise in the local
oscillator section of a
receiver?
E4C01
It can cause strong
signals on nearby
frequencies to
interfere with weak
signals
back
What xmtr freqs.
would cause an IMproduct signal in a rcvr
tuned to 146.70 MHz
when a nearby stn
xmits on 146.52 MHz?
E4D05
146.34 MHz and
146.61 MHz
back
How does the
beamwidth of an
antenna vary as the
gain is increased?
E9D03
It decreases
back
What are the
disadvantages of a
terminated
rhombic antenna
for the HF bands?
E9C05
The antenna
requires a large
physical area and 4
separate supports.
back
What is an
advantage of using
a shielded loop
antenna for
direction finding?
E9H12
It is electrostatically balanced
against ground,
giving better nulls.
back
What’s the
approx. maximum
separation between
2 stations QSOing by
Moon bounce?
E3A01
12,000 miles, as
long as both can
“see” the Moon
back
What 3rd family
of circles is often
added to a Smith
chart while solving
a problem?
E9G09
Standing-wave
ratio circles
back
Semi-final
Jepperdee
topic:
”satellite
vocabulary”
Your wager?
What is the name
of the location in a
satellite’s orbit
which is farthest
from Earth?
apogee
(to second game board)
Final
Jepperdee
topic:
”meteor-satter
communications”
How much will you
risk?
What range of
amateur frequencies
is well suited for
meteor-scatter
communications?
E3A09
28 - 148 MHz
Thanks for playing
Exam-prep
Jepperdee:
Extra-class
Edition, v. 2
The producer welcomes feedback………[email protected]
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