QSK has been with us for at least 50 years.


I’ve used it that long myself.  I'm not sure when it orignated.

Unfortunately it is still very much misunderstood.


What exactly is QSK?


Simply put, QSK is a method of operating CW mode, which enables the operator to listen between pauses while sending CW.  Listening between the pauses can have many advantages, as far as operating goes.  But as we will see, it often brings with it a string of disadvantages.


What are the advantages of QSK?


By being able to listen between the pauses, we have several advantages which may or may not be useful to your everyday operations:

  • When calling in a pileup, we can hear if someone else is calling and better time the instance that we slip our own call in.  This increases our chances of the DX station hearing our call.
  • When working traffic nets and passing traffic, QSK enables instantaneous interrupts to request "fills" (repeats of data we have missed) in the messages.
  • When calling another station, if that station comes back to another OM while we are still calling, we hear that he is transmitting and cease our transmission immediately.  This reduces QRM (by us) on the band.


In addition, transceiver setup properly to run full QSK with a linear amplifier assure a clean operation of the hardware.  The first "dit" in not chopped off on the front end, the relays inside the amplifier do not arc from RF being applied too soon, etc.   


Do we really need QSK?


Many people think so.  IMO, by its definition, "full" QSK is overkill for everyone. I'm not really proposing a slow Semi-BK but rather something in between. I will show you that below in the text that follows. Something close to QSK can be very advantages for everyone, and comes at a far lessor cost than FULL QSK!


Are ther any disadvantages of QSK?


Yes; for us humans:  You could almost say it depends on the age of the operator. (hi).   Although full QSK has many advantages, it also brings with it some disadvantages.  In normal casual operating when you are transmitting, you don't wish to be disturbed by static and other noise that you might hear during transmission pauses.  These are not only distracting, they can be very nerve-racking.  Not running QSK can be a very welcome feature, sometimes. 


Technically:  If all hardware were supplied by on single manufacturer, I'm sure QSK would be easy to implement.  Unfortunately most hams usually have varies components from different manufacturers.  There is no standadization on interfacing and often the configuration does not interface seemlessly together.  As a result we see a lot of hot switching, resulting in on the air key clicks being generated and eventually the burning of our amplifier's relay contacts.  For more info on why this is, see  CW AMP SEQUENCING .





Full QSK means that the operator can actually hear in between dits. The length in between dits is equal to the length of a dit and  depends on the speed we are operating at.  At 24 wpm a dit is about 100 mS long, or 1/10 of a second.


Do we really need to hear in between dits?


Suppose we accept that we do not need to hear in between dits "if" we can at least hear in between characters.  The character spacing is 3x the dit spacing or about 300 mS in our example of 24 wpm.


I suggest that compared to the reaction time of a human operator, it makes no significant difference whether we are able to hear in between dits or just in between characters.


The ability to hear in between characters enables us to keep a watch on our TX frequency while we are transmitting, for all practical purposes, just as well as we could when hearing in between dits.  This is the primary goal of the concept of QSK, therefore I suggest that Near-QSK is "good enough."



By accepting this (IMO) insignificant compromise for the human,

we open a new world of [timing] opportunity for the electronics.  


This compromise will enable us to completely avoid hot switching, even when using older open-fram relay technology in our amplifiers.




 To be continued . . . (maybe)