E2E01:

Which type of modulation is common for data emissions below 30 MHz?

  1. DTMF tones modulating an FM signal
  2. FSK
  3. Pulse modulation
  4. Spread spectrum

E2E02:

What do the letters FEC mean as they relate to digital operation?

  1. Forward Error Correction
  2. First Error Correction
  3. Fatal Error Correction
  4. Final Error Correction

E2E03:

How is the timing of JT65 contacts organized?

  1. By exchanging ACK/NAK packets
  2. Stations take turns on alternate days
  3. Alternating transmissions at 1 minute intervals
  4. It depends on the lunar phase

E2E04:

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

  1. Selective fading has occurred
  2. One of the signal filters is saturated
  3. The receiver has drifted 5 kHz from the desired receive frequency
  4. The mark and space signal have been inverted

E2E05:

Which type of digital mode does not support keyboard-to-keyboard operation?

  1. Winlink
  2. RTTY
  3. PSK31
  4. MFSK

E2E06:

What is the most common data rate used for HF packet?

  1. 48 baud
  2. 110 baud
  3. 300 baud
  4. 1200 baud

E2E07:

What is the typical bandwidth of a properly modulated MFSK16 signal?

  1. 31 Hz
  2. 316 Hz
  3. 550 Hz
  4. 2.16 kHz

E2E08:

Which of the following HF digital modes can be used to transfer binary files?

  1. Hellschreiber
  2. PACTOR
  3. RTTY
  4. AMTOR

E2E09:

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

  1. RTTY
  2. PACTOR
  3. MT63
  4. PSK31

E2E10:

Which of these digital modes has the narrowest bandwidth?

  1. MFSK16
  2. 170 Hz shift, 45 baud RTTY
  3. PSK31
  4. 300-baud packet

E2E11:

What is the difference between direct FSK and audio FSK?

  1. Direct FSK applies the data signal to the transmitter VFO
  2. Audio FSK has a superior frequency response
  3. Direct FSK uses a DC-coupled data connection
  4. Audio FSK can be performed anywhere in the transmit chain

E2E12:

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

  1. Local
  2. Remote
  3. Automatic
  4. ALE can use any type of control

E2E13:

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

  1. Your transmit frequency is incorrect
  2. The protocol version you are using is not supported by the digital station
  3. Another station you are unable to hear is using the frequency
  4. All of these choices are correct