An answer on Basic QSO format? mentions things like "QRM" and "QSB". What do those terms mean?


"QRM" is one of many Q-codes used as abbreviations in radio communication. "QRM" in particular refers to human-generated interference (as opposed to "QRN" which is used to refer to atmospheric noise). "QSB" refers to fading (variation in signal strength over time).

The codes originated from the desire to keep CW (morse code) transmissions as brief as possible due to the format's inherent bandwidth limits, but have stuck around and now often show up as abbreviations in regular conversation as well.

  • $\begingroup$ yeah, sorry; should've been clearer in my answer. $\endgroup$
    – scruss
    Oct 23 '13 at 2:19
  • 2
    $\begingroup$ No worries. I think there's a general tendency in the ham community to tend towards jargon; I just like to help make stuff more approachable for people who aren't as familiar with the lay of the land. $\endgroup$
    – Amber
    Oct 23 '13 at 5:51

I keep these "Q" signals in line with this :

  • QRN is "N"atural band noise ( lightning )
  • QRM is "M"an-made band noise ( crowded signals )
  • QSB is "B"utterfly effect from Ionosphere in-stability.
  • 2
    $\begingroup$ That's a good way to remember them! Also, here on Stack Exchange, we don't put signatures on posts — the user card automatically provided at the bottom is your signature, and you can put whatever you like in your name and profile. I've made these changes for you. $\endgroup$
    – Mike Waters
    Dec 18 '19 at 19:07

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.