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
[youtube=http://www.youtube.com/watch?v=eNmSSgCqDPM&w=470]
Carpal Tunnel Syndrome, not Carpel…
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.
Shades of the past!
I used to have a Heathkit keyer like this:
http://morsetelegraphkey.com/wp-content/uploads/2011/09/-291992906077702220.jpg
You can do the same thing with a TI Lauchpad: http://dbindner.freeshell.org/msp430/cw.html
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.”
So where is the rig interface? Without that it’s not a keyer. And BTW what does HAM stand for? ;)
HAM doesn’t stand for anything. It was originally used to refer to the fact that amateur radio users would stomp all over everyone else’s signals and were considered “ham-fisted” (or so I’ve been lead to believe).
You can read a similarly condensed history here: http://www.arrl.org/ham-radio-history
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]
sadly CW keys is only thing that HAMs are building nowadays
That’s simply not true therian – there’s a thriving home-brew scene here in the UK, including ‘buildathons’ where newcomers to construction are mentored by more experienced constructors to ensure a successful result…
http://www.southgatearc.org/news/october2011/5th_bath_buildathon.htm
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.
Speak for yourself, I build alot of different QRP rigs. Many fellow hams are also building.
Can you made anything simple without Arduino, eeproms, processors? I has keyer long time before this. Kids will need PC to light a fire in the fireplace.
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
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)
Thought you might be interested in my ATTINY85 keyer! http://projectmf.homelinux.com/keyer/ and https://www.youtube.com/watch?v=Ol6krttaOy0
73,
Don
WD9DMP
Hello, unfortunately the links are broken, so I have no idea of who Dimitris is: I would like to see his code. I have tried to write to the Web site that hosted the page, hoping to get some info. If anyone knows…. Thanks. Giorgio giorgio . denunzio (at) unisalento . it