Transcript Serious ‘XM (That’s W2XM) presents

Serious ‘XM
(That’s W2XM)
presents
Exam-prep Jepperdee:
Extra-class Edition
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 screen until you see the next hyperlink.
There is one daily double on each board; click on “Here’s the
question.”
For most fun, appropriate hardware (lights, push-buttons,
sounder, lockout circuitry) should be used. A diagram is available from
the author.
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
During a VHFUHF contest, in which
band segment would
you expect to find the
highest level of
activity?
E2C06
The weak-signal
segment of the
band, with most of
the activity near the
calling frequency
back
E2C07
What is the
Cabrillo format?
A standard for
submission of
electronic contest
logs
back
Which digital
protocol is used by
APRS: PACTOR,
E2D07
802.11, AX.25, or
AMTOR?
AX.25
back
What is the
direction of a
descending pass for
an amateur
satellite?
E2A02
From north to
south
back
What do the
terms L band and S
band specify with
regard to satellite
communications?
E2A09
The 23-cm and
13-cm bands
back
What is the
maximum power
output permitted
on the 60 meter
band?
E1A05
100 watts PEP
effective radiated
power relative to
the gain of a halfwave dipole
back
What is a
remotely
controlled
station?
E1C01
A station controlled
indirectly through a
control link
back
Which VHF
amateur-service
bands have
frequencies available
for space stations?
E1D08
2 meters
back
When/why
might the FCC issue
"Special Temporary
Authority" (STA) to
an amateur station?
E1F14
To provide for
experimental
amateur
communications
back
What is the
maximum
bandwidth for a
data emission on
60 meters?
E1B05
2.8 kHz
back
Why use
powdered-iron
toroids rather than
ferrite ones in an
inductor?
E6D08
Powdered-iron
toroids generally
maintain their
characteristics at
higher currents
back
What is the time
constant of a circuit
having two 220-μF
caps and two 1-MΩ
res., all in parallel?
E5B04
220 seconds
back
What is the
phase between the
I through and the
v across a series
resonant circuit?
E5A08
The voltage and
current are in
phase
back
Expressed in
polar, what is the z of
a 400-Ω reactance
cap in series with a
300-Ω resistor?
E5C04
500 ohms at an
angle of -53.1
degrees
back
How many watts
are consumed in a
circuit having a p.f. of
0.2 if the input is
100-V AC at 4 A?
E5D12
80 watts
back
What do we call
the freq. at which the
grounded-base current gain of a transistor is .7 X the gain at
1 kHz?
E6A08
alpha cutoff
frequency
back
What characteristics of the MMIC
make it a good choice
for VHF-throughmicrowave circuits?
E6E06
Controlled gain, low
noise figure, &
constant in and out
Z’s over a given
frequency range
back
What type of CRT
deflection is best
when high-frequency
waveforms are to be
displayed?
E6D13
Electrostatic
back
What type of
semiconductor
device is used as a
voltage-controlled
capacitor?
E6B04
Varactor diode
back
What property of
the core material
determines the
inductance of a
toroidal inductor?
E6D06
Permeability
back
E7B12
What
is this?
Figure E7-1
Common emitter
amplifier
back
What is the
equivalent circuit
of a quartz
crystal?
E6E10
Motional C, motional
L, and loss R all in
series; with a shunt C
representing electrode and stray C
back
Define
“capture range”
of a phase-locked
loop circuit?
E7H13
The frequency
range over which
the circuit can lock
back
What kind of filter
would attenuate an
interfering signal as
you are receiving an
SSB transmission?
E7C07
A notch filter
back
E7D13
Purpose of D1?
Figure E7- 3
Q1
+25
C1
4000
C2
4000
+12
C3
0.01
R1
D1
R2
To provide a
voltage reference
back
What is the typical nominal value for
the RMS voltage at a
standard household
a.c. power outlet?
E8D15
120V
back
What is the
approximate ratio
of PEP-to-average
power in a typical
SSB phone signal?
E8A06
2.5 to 1
back
Which would a
spectrum analyzer
display on the vertical
axis: Amplitude,
E4A03
Duration, SWR, or Q?
Amplitude
back
What parameter
is varied by the
modulating signal in
a pulse-position
modulation system?
E8B08
The time at which
each pulse occurs
back
How can you
determine if linenoise interference is
being generated
within your home?
E4E07
By turning off the
AC-power main
breaker and listening on a battery
operated radio
back
How does JT65
improve EME
communications?
E2D12
It can decode
signals many dB
below the noise
floor using FEC
back
What is the
necessary bandwidth
of a 13-WPM
international Morse
code transmission?
E8C05
Approximately 52
Hz
back
What hardware,
besides a receiver &
computer, is needed
to decode SSTV using
E2B09
Digital Radio Mondiale
(DRM)?
No other
hardware is
needed
back
What is the
definition of the
“noise figure” of
a receiver?
E4C04
The ratio of the
noise generated by
the receiver to the
theoretical minimum noise (in dB)
back
What noise
figure value might
be typical of a lownoise UHF
preamplifier?
E6E05
2 dB
back
E9A09
What is meant
by antenna
bandwidth?
The frequency
range over which
an antenna satisfies
a performance
requirement
back
What happens to
Z at the feed point of
a fixed-length ant. as
the frequency of
operation is lowered?
E9D13
The radiation resistance decreases &
the capacitive
reactance
increases.
back
What is the
approx. length of an
air-insulated parallel
conductor xmission
line that is λ/2 long at
14.1 MHz?
E9F06
10 meters
back
What is the
approx. maximum
range for signals
using transequatorial
propagation?
E3B02
5000 miles
back
How may dangerous levels of carbon monoxide from
an emergency generator be detected?
E0A07
Only with a carbon
monoxide detector
back
Semi-final
Jepperdee
topic:
A.C. waveform
For a sinusoidal
voltage, how do
the peak and rms
values compare?
peak voltage =
1.414 X rms voltage
OR
Vrms = .707 X Vpeak
(to second game board)
Final
Jepperdee
topic:
hazardous
materials
Which insulating
material used as a
thermal conductor is
extremely toxic if
broken or crushed and
accidentally inhaled?
E0A09
Beryllium Oxide
Thanks for playing
Exam-prep
Jepperdee:
Extra-class
Edition