The Knee-Slapper Key

If necessity is the mother of invention, ham radio must be closely related.

The SKCC weekend sprint in August 2020 had a special theme of home-brew keys. Friday, less than a day before it started, I decided to try making a key.

I had no design in mind and didn’t want to do something cliche’.  I ended up looking through a junk box of old hardware from various pieces of furniture destroyed long ago.  I saw a “drawer pull” or handle…  and thought “that could be interesting.”  Then I found two pieces of metal (brass, maybe, and pre-drilled!).  

My vision was that I could send simply by squeezing the ‘key’ in my hand; not as easy as I thought.  I ended up holding it on top of my leg and sending somewhat normally. It worked well with little arm fatigue. Below is a picture of the key being held upside down so you can seen the brilliant design and amazing craftsmanship.  

If you want to see it in action (I used it to make 78 QSOs and call CQ many times, as well), check out my first ever YouTube video — all 28 seconds worth:

I’ve come to think of it as the ‘knee slapper’ key, though it isn’t keyed with a slapping motion 😉  One caution and call for future design improvements:  I wore a hole in a pair of shorts before I realized I needed something under it; the metal contact/spring pieces were too much for my old shorts….  A piece of that rubbery non-skid shelf liner stuff did the trick.

So, if Necessity is the mother of invention, here’s to invention’s brother-in-law — Ham Radio! – Jim AF3Z