SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/hame-frequency-hopping

Which describes spread spectrum frequency hopping?

Rapidly changing frequency in a pseudorandom sequence.

Start playing free

  1. The receiver asks the transmitter to change frequency
  2. Rapidly changing frequency in a pseudorandom sequence ✔
  3. A bit stream shifts the carrier phase pseudorandomly

Why: The transmitter jumps between frequencies in a pattern the receiver also knows. Interference on any one frequency only hits a small part of the message.

Huh, didn't know that: Direct sequence spread spectrum uses a high-speed binary bit stream to shift the phase of an RF carrier (E8D02).

The dad joke
What should you do when the music on a shortwave radio gets boring? Try a different band.
Like this card?
Play the game

References

Answer: Rapidly changing frequency in a pseudorandom sequence. The transmitter jumps between frequencies in a pattern the receiver also knows. Interference on any one frequency only hits a small part of the message.

  1. NCVEC 2024-2028 Amateur Extra Question Pool, 4th Errata (Feb 4, 2026) ncvec.org/downloads/2024-2028%20Extra%20Class%20Question%20Pool%20and%20Syllabus%20Public%20Release%20with%204th%20Errata%20Feb%204%202026.pdf
    D. Rapidly varying the frequency of a transmitted signal according to a pseudorandom sequence
    Checked 2026-10-11.

Think this answer is wrong? Tap "Challenge this answer" on the card in the game and tell us why.

Test yourself in the game

Ham RadioHow long is one FT8 transmit/receive sequence?Ham RadioHow long is one WSPR transmitting period?Ham RadioThe Q65 mode is designed for which kind of signal conditions?

That's stuff everyone should know.