Saturday, October 30, 2010

Homebrew Straight Key



 I first became interested in radio in the 1990's.  Back then I had a table top shortwave receiver with which I discovered the amateur bands.  I was intrigued with the many Morse Code signals I could hear, some slow and some fast but all of them unintelligible to me.  I had no idea how the amateur operators could make sense out of the endless stream of beeps flying around the ether but I knew I wanted to be a part of that someday.

In the back of a CQ magazine was a tiny two inch add displaying telegraph keys for sale.  There was two keys pictured in black and white.  As I have mentioned before woodworking is a hobby of mine so I chose the key that I liked the best of the two and went to work estimating dimensions as well as I could from that little add.  I don't recall any of the details from the add except that the keys appeared to be made of brass.

At that time I knew as little about telegraph keys as I did the code itself so I had to engineer the electrical parts and the mechanics of the key on my own.  Screwed to the bottom surface of the lever is s thin strip of brass that runs the length of the lever to complete the circuit when the lever is depressed closing the contacts. The trunnion is simply a piece of hardwood dowel I turned on the lathe until it fit smoothly into bronze bushings. The wood is various species of tropical hardwood with the lever and trunnion supports being made from Honduran Mahogany.  The knob I made from American Walnut salvaged from a local church that was being remodeled.  That piece of walnut is easily over 100 years old. The key functions fine and I will put it on the air for the first time during the November SKCC Week End Sprint which happens to be the 2010 Craftsman's key Sprint.

If anyone recognizes the design I would love to know who was making and selling the keys I saw years ago in that CQ magazine that inspired me down the road to amateur radio and Morse Code radiotelegraphy.   

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