"DOUBLE LEVER PADDLE"
built by Carel Mulder PA0CMU

As mentioned in the write up of my version of NB6M's paddle, I would like to build a double paddle version using Wayne's idea as a foundation.

Some days ago Wayne and I emailed each other a few times, exchanging views about this easy to build PC-board paddles.

Wayne wrote me: "As for the design of the double paddle. Why not have an upright screw or other contact in between the two paddles, and leave the spacing for each one (away from the center screw or contact) just a little greater than you want when you solder the two paddles into place."

Then, after enlarging or adjusting the holes in the paddles for whatever tension you want, you could use the two adjustment screws just as I have them for the single paddle, but they would push each paddle closer to the central upright screw. All you would have to do would be to make an insulating cut on each side of the screw supports in order to insulate the distance adjustment screws from ground, and it would work fine."

The idea of the upright screw seemed to be nice, but as mentioned earlier, I use a Bencher BY-1 with a paddle-distance of about 1/2" and I am used to that. Of course I could use two screws, but considered that using PC-board was also possible.

As you can see on the pictures, I made a "H" from small pieces of PC-board. Because PC-board against PC-board doesn't make reliable contact, I soldered two contact points of an old, but never used, relay to the board. The next description counts on the enlarging of the witdh of the paddle by 1/2". If you prefer another paddle-distance, change the dimensions of the base plate, rear frame and (contact point) partition board.

Using the pictures as a guide, first cut out and shape the parts made from PC board material. Enlarge the dimensions of the base plate to 2" x 2", and the rear panel to 5/8" x 1 5/8" (my rear panel is somewhat higher to create more space for my fingers!). So the adjustment screw supports become 3/8" x 5/8" and the contact point supports are 9/32" x 17/32". The partition board is 1/4" x 17/32" and is depends on the dimensions of the relay contacts. Determine it yourself.

Follow Wayne's description about drilling, filing and so on. With a pencil draw two axes. One from front to rear in the middle of the base plate and one from left to right also in the middle. This is the axis where the adjustment supports are soldered later.

The relay contacts I used where nailed on a copper strip (see picture). With a wire-cutter cut the contact point to a circle of about 7/32", remove the wire-edge with a file, drill a little hole in the contact point supports at 3/8" from the bottom to let the nailed part of the contact sink into the PC-board and solder the contact point to the support.

Set the rear panel in place, centered, and tack solder one edge. Mount as described by Wayne. Next, assemble and solder the adjustment screw supports remembering the enlarging of the width by 1/2".

Now, at the intersection point of the two drawn axes, solder the contact point partition perpendicular to the base, then, mount the two contact point supports to the base plate and partition board. Check visually for proper placement!! The "H" should be exactly in the middle of the base plate.

Finally, place the first paddle in position between the adjustment screw and contact point butted up against the rear frame. The upper edge of the paddle should be equal to the top of the rear panel.

As Wayne wrote: "Finger tighten the adjustment screw against the paddle, which will hold the paddle pretty well in position while you then tack solder each side of the paddle against the rear frame and then run a bead of solder along the edge of each side of the paddle where it butts against the rear frame." Don't forget to place some piece of material (paper, plastic) between the paddle and contactpoint relativ to the desired contactdistance you want.

Try to realize the most accurate desired contact space without adjusting the screws because the adjustment screw will increase the tension in the paddle! Repeat for the second paddle.

Now, adjust the screws for an equal dit and dah space. Use phone plugs for wiring up the paddle or solder the wire directly to the paddle as I did. It's up to you.

The fantastic world of QRP exist due too the use of CW. When CW dies down, QRP is QRT!

Enjoy CW the next century, perhaps with the help of these easy to build PC-board paddles.

73,


Carel, PA0CMU.