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I'm reading Rec. ITU-R M.1172 and its precise definition of Q-code QSD is "Are my signals mutilated? Your signals are mutilated."

From what I've seen, QSD is usually used to check if keying is defective, but this is the first time I've seen word "mutilated" used to describe defectiveness.

So my question is: Is there any deeper meaning to mutilated other than defective here?

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    $\begingroup$ I think it means you have time-traveled to the early 20th century. $\endgroup$ – Phil Frost - W8II Apr 19 '15 at 20:38
  • $\begingroup$ @Phil Frost Incredible! And my time machine even lets me connect to the Internet! $\endgroup$ – AndrejaKo Apr 19 '15 at 21:44
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    $\begingroup$ In some documents QSD means "Is my keying defective/Your keying is defective" itu.int/dms_pub/itu-s/oth/02/02/S02020000044502PDFE.pdf IMHO, one can alternately use both meanings. I do think the "defective" meaning is more appropriate and easier to remember/understand. $\endgroup$ – sessyargc.jp Apr 19 '15 at 23:40
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Wikipedia explains this with a second option for QSD.

Is my keying defective? [AP13] or Are my signals mutilated? [AP14]

So essentially it means, is your keying having some kind of an issue. This could be the result of a defective keyer. Essentially it means is there something going on that's cutting off the signal?

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Back in the day, it wasn't uncommon for the key to directly switch the transmitter. Transistors didn't exist, and why would you use a relay when you already have a perfectly good switch under your fingers?

Also back in the day, it wasn't uncommon to transmit with a whole ton of power. Building a bigger transmitter is technologically less challenging than building a more sensitive receiver.

So, the full power of a very large transmitter going through your key -- you might imagine what happens. Between mechanical wear from sending all those telegrams, and arcing from using a key to switch many kilowatts of transmitter power (probably with no attempt to suppress the inductive arcing), the key contacts inevitably get mutilated. Imagine what a resistive, scratchy, intermittent switch contact does to your signal. "Mutilated" seems like as apt an adjective than any.

These days the switching is done with relays or transistors, so if you encounter "QSD", the most likely explanation is that you have traveled back in time to the early 20th century.

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