An Iambic Keyer In 5 Minutes

When most people think about a telegraph key, a piece of 1890s tech with a lever that moves up and down comes to mind. These ‘straight keys’ were terrible for telegraphers and led to repetitive stress injuries like carpel tunnel syndrome..Iambic keys came along and move the contacts to a horizontal position. If you ever see a HAM playing with his CW rig, chances are they’re using an iambic key. It’s great, then, that you can build your own iambic key in five minutes using parts you have lying around.

The build [Dimitris] put up is dead simple – just two metal contacts with a pair of 470K pullup resistors. All this connects to three pins on an Arduino. All the micocontroller needs to do is measure the rise time a touch sensor pin when a voltage is applied. If there’s a finger on the pin, the capacitance increases and the rise time is longer. After that, just assign one sensor as ‘dit’ and the other as ‘dah’ and you’ve got an iambic key.

[Dimitris] put all the code for his project up on his blog. His iambic key seems like the perfect project after a tiny Morse trainer. Check out the video of the key in action after the break

16 thoughts on “An Iambic Keyer In 5 Minutes

  1. The CTD Risk Index (cumulative trauma disorder for those of you not in the biz) looks at a variety of repetitive motions, and a horizontal pinch can be just as damaging as other motions. Yes, there isn’t as much impact to your fingers with this build, but making repetetive movements has potenital to injure no matter what you’re doing.

    Neat build though.

  2. Tried learning CW in High School, but couldn’t pass the test ’cause I couldn’t send with a key. I could with a “bug” which was the mechanical version of that dealy.

    “Dad,” my younger son once said, “you have the coordination of a philodendron.”

      1. The question was posted in friendly sarcastic manner. I have pointed our several times simply ham suffices for the common nick name for amateur radio operators and HAM is not an acronym for anything related to amateur radio, as far as I know anyway [shrug]

    1. Evidently you aren’t in a position to see what hams build. Yes not as many hams aren’t into to DIY as in years past. That’s not any different the than DIY being down in the general population overall.

    1. Yea, yea.. we all read that before. :) Most use methods other than flint or friction methods to light the fire place these days. Computer used electron tubes. Time move on my friend

  3. Wow ! I got my ticket 38 yrs ago here in Brazil.
    I love speedy CW using my ears (two – of course…hi) and loved this one !
    Boy ! When I become CW fan at 17 yrs old I do it with a “Sideswiper” thing because of speed…
    ( search on Google abt it ), and today in LESS THAN 5 MINUTES I got high speed right from the box !

    73/DX and
    See Ya on the Bands (all of them !),
    PP5VX (Bone)

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