Homebrew Single-Lever CW Paddle

from Mark M. Oring, AG4RQ onNovember 10, 2006

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AG4RQ’s Homebrew Single-Lever CW Paddle

• Six junk CD’s or a 5" x 5" piece of plywood.
• Four small machine screws with matching nuts. Screws should be justlong enough to go through the CD’s with enough threads sticking up forthe nuts to fasten them.
• A medium size machine screw and nut.
• Four longer machine screws about 3/4 inch long with 6 matching nuts.
• Two star washers.
• The metal faceplate from a computer card (the part that bolts to the computer case).
• Double-sided adhesive foam tape from Radio Shack.
• A wooden double-sided ice cream spoon or thick popsicle stick.
• Two wire ties.
• Scrap steel that can be bent with locking pliers.
• A spool of two-conductor shielded wire.
• A 1/4" stereo plug.
• Four rubber feet.
• A drill with bits for drilling steel.
• Locking pliers.

Building the Paddle:

Drill four holes about 1/4" from the edge of the CD’s. Use the foursmall screws and nuts to bolt the CD’s together. If using plywood, thisstep is obviously not needed. Take a small piece of scrap metal andmake a 90-degree angle bracket. Drill 2 holes in the angle bracket.Bolt one side of the angle bracket to the top of the CD’s. The otherhole in the angle bracket should be perpendicular to the CD’s.

Take a metal cutter or pliers and cut off or break off theperpendicular stubs from the metal computer card faceplate. These stubsare where the screws fasten the computer card to the faceplate. Theyonly get in the way, so cut them off. Bend the end tab of the faceplatestraight. They are all on a slight angle so they fit into the slot of acomputer case.

Use the medium size screw and its matching nut along with the 2 starwashers to fasten the computer card faceplate to the other hole in theangle bracket. Make 2 more angle brackets larger than the first one.Drill a hole in each end of the angle brackets. At the bottom of theCD’s, about 1" up from the end of the computer card faceplate, drillholes in the CD’s 3/4” from the computer card faceplate, and fasten theangle brackets to the CD’s. Place a nut on each screw all the way up.Slide each screw through each angle bracket and fasten with the othernuts. The computer card faceplate should rest evenly between bothscrews. Use these screws and their nuts to adjust the distance betweenthe screws and the computer card faceplate.

Cut a length (length is your choice) of the two-conductor shieldedwire. Attach the stereo plug to one end. Make a note of which colorwire is connected to the tip and which color wire is connected to thering. At the other end, you should have a short stub of shield and two5" lengths of of insulated wire. Solder the shield to the top anglebracket that the computer card faceplate is attached to. The wire thatis connected to the ring of the stereo plug needs to be soldered to theangle bracket on the left side (dahs). The wire that is connected tothe tip of the stereo plug needs to be soldered to the angle bracket onthe right side (dits).

Take your double-sided ice cream spoon and cut it in half. Take 3/4" ofthe double-sided foam tape and place on both sides at the end of thecomputer card faceplate. Stick the 2 ice cream spoon halves to thetape. The spoon halves should be on both sides of the computer cardfaceplate. Fasten with 2 wire ties. It would be a good idea to eitherglue or fasten the bottom of the paddle to the table or a larger pieceof wood to keep it from moving around when you use it. What I do is puta couple of weights on top on both sides of the CD’s to keep it frommoving around. I like mine portable.

The operation of this paddle is similar to any single-lever paddleattached to an electronic keyer. It is not iambic. But it works quitewell for the minimal investment you make to build it. Mine originallydidn’t cost a dime to build. I originally used a junk CB mike cord thatjust happened to have a stereo plug on the end. Some of the older CB’sused a ¼” stereo plug for the mic connector. I later decided to go toRadio Shack to buy the spool of shielded 2-conductor wire and thestereo plug because I wanted a 12-foot cable rather than a 5-footcoiled CB mic cord. Nothing can take the place of a finelyprecision-made professional paddle or bug, but if you’re short on cash,or just like to homebrew stuff, this will work quite well. 73.

출처:http://www.eham.net/articles/15184