E8C Digital signals: CW; baudot; ASCII;
packet; AMTOR; Clover;
information rate vs bandwidth
E8C01
(D)
What
digital code consists of elements having unequal length?
A. ASCII
B. AX.25
C. Baudot
D. Morse code
E8C02
(B)
What
are some of the differences between the Baudot digital code and ASCII?
A. Baudot uses four data bits per character,
ASCII uses eight; Baudot uses one character as a shift code, ASCII has no shift
code
B. Baudot uses five data
bits per character, ASCII uses eight; Baudot uses one character as a shift
code, ASCII has no shift code
C. Baudot uses six data bits per character,
ASCII uses eight; Baudot has no shift code, ASCII uses one character as a shift
code
D. Baudot uses seven data bits per character,
ASCII uses eight; Baudot has no shift code, ASCII uses one character as a shift
code
E8C03
(C)
What is
one advantage of using the ASCII code for data communications?
A. It includes built-in error-correction
features
B. It contains fewer information bits per
character than any other code
C. It is possible to
transmit both upper and lower case text
D. It uses one character as a "shift"
code to send numeric and special characters
E8C04
(B)
What
digital communications system is well suited for meteor-scatter communications?
A. ACSSB
B. Packet radio
C. AMTOR
D. Spread spectrum
E8C05
(D)
What
type of error control system does Mode A AMTOR use?
A. Each character is sent twice
B. The receiving station checks the calculated
frame check sequence (FCS) against the transmitted FCS
C. The receiving station checks the calculated
frame parity against the transmitted parity
D. The receiving station
automatically requests repeats when needed
E8C06
(A)
What
type of error control system does Mode B AMTOR use?
A. Each character is sent
twice
B. The receiving station checks the calculated
frame check sequence (FCS) against the transmitted FCS
C. The receiving station checks the calculated
frame parity against the transmitted parity
D. The receiving station automatically requests
repeats when needed
E8C07
(C)
What is
the necessary bandwidth of a 13-WPM international Morse code emission A1A
transmission?
A. Approximately 13 Hz
B. Approximately 26 Hz
C. Approximately 52 Hz
D. Approximately 104 Hz
E8C08
(C)
What is
the necessary bandwidth for a 170-hertz shift, 300-baud ASCII emission J2D
transmission?
A. 0 Hz
B. 0.3 kHz
C. 0.5 kHz
D. 1.0 kHz
E8C09
(D)
What is
the necessary bandwidth of a 1000-Hz shift, 1200-baud ASCII emission F1D
transmission?
A. 1000 Hz
B. 1200 Hz
C. 440 Hz
D. 2400 Hz
E8C10
(A)
What is
the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII emission
F1D transmission?
A. 15.36 kHz
B. 9.6 kHz
C. 4.8 kHz
D. 5.76 kHz