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+E2E Operating methods: digital modes and procedures for HF
+
+- [[E2E01]] (B)
+Which of the following types of modulation is used for data emissions below 30 MHz? #card
+	- [[A.]] DTMF tones modulating an FM signal
+	- [[B.]] FSK
+	- [[C.]] Pulse modulation
+	- [[D.]] Spread spectrum
+--
+- [[E2E02]] (B)
+Which of the following synchronizes WSJT-X digital mode transmit/receive timing? #card
+	- [[A.]] Alignment of frequency shifts
+	- [[B.]] Synchronization of computer clocks
+	- [[C.]] Sync-field transmission
+	- [[D.]] Sync-pulse timing
+--
+- [[E2E03]] (B)
+To what does the "4" in FT4 refer? #card
+	- [[A.]] Multiples of 4 bits of user information
+	- [[B.]] Four-tone continuous-phase frequency shift keying
+	- [[C.]] Four transmit/receive cycles per minute
+	- [[D.]] All these choices are correct
+--
+- [[E2E04]] (D)
+Which of the following is characteristic of the FST4 mode? #card
+	- [[A.]] Four-tone Gaussian frequency shift keying
+	- [[B.]] Variable transmit/receive periods
+	- [[C.]] Seven different tone spacings
+	- [[D.]] All these choices are correct
+--
+- [[E2E05]] (A)
+Which of these digital modes does not support keyboard-to-keyboard operation? #card
+	- [[A.]] WSPR
+	- [[B.]] RTTY
+	- [[C.]] PSK31
+	- [[D.]] MFSK16
+--
+- [[E2E06]] (C)
+What is the length of an FT8 transmission cycle? #card
+	- [[A.]] It varies with the amount of data
+	- [[B.]] 8 seconds
+	- [[C.]] 15 seconds
+	- [[D.]] 30 seconds
+--
+- [[E2E07]] (C)
+How does Q65 differ from JT65? #card
+	- [[A.]] Keyboard-to keyboard operation is supported
+	- [[B.]] Quadrature modulation is used
+	- [[C.]] Multiple receive cycles are averaged
+	- [[D.]] All these choices are correct
+--
+- [[E2E08]] (B)
+Which of the following HF digital modes can be used to transfer binary files? #card
+	- [[A.]] PSK31
+	- [[B.]] PACTOR
+	- [[C.]] RTTY
+	- [[D.]] AMTOR
+--
+- [[E2E09]] (D)
+Which of the following HF digital modes uses variable-length character coding? #card
+	- [[A.]] RTTY
+	- [[B.]] PACTOR
+	- [[C.]] MT63
+	- [[D.]] PSK31
+--
+- [[E2E10]] (C)
+Which of these digital modes has the narrowest bandwidth? #card
+	- [[A.]] MFSK16
+	- [[B.]] 170 Hz shift, 45-baud RTTY
+	- [[C.]] FT8
+	- [[D.]] PACTOR IV
+--
+- [[E2E11]] (A)
+What is the difference between direct FSK and audio FSK? #card
+	- [[A.]] Direct FSK modulates the transmitter VFO
+	- [[B.]] Direct FSK occupies less bandwidth
+	- [[C.]] Direct FSK can transmit higher baud rates
+	- [[D.]] All these choices are correct
+--
+- [[E2E12]] (A)
+How do ALE stations establish contact? #card
+	- [[A.]] ALE constantly scans a list of frequencies, activating the radio when the designated call sign is received
+	- [[B.]] ALE radios monitor an internet site for the frequency they are being paged on
+	- [[C.]] ALE radios send a constant tone code to establish a frequency for future use
+	- [[D.]] ALE radios activate when they hear their signal echoed by back scatter
+--
+- [[E2E13]] (D)
+Which of these digital modes has the highest data throughput under clear communication conditions? #card
+	- [[A.]] MFSK16
+	- [[B.]] 170 Hz shift, 45 baud RTTY
+	- [[C.]] FT8
+	- [[D.]] PACTOR IV