A Simple ‘Iambic Paddle’ for Travelers

From : Charles & Sandra Cohen

Scott —

Sorry, no parts list. And the bottom is covered by silicone rubber, so a photo won’t help you.

Radio Shack should have everything except maybe the two switches. Those, you could get at any electronic parts distributor as “tactile switches”. They come in various sizes. Mine are 12mm square, with a 160 gm activation force. (less activation force would be better, but I wouldn’t want anything smaller).

The top of my phone jack was transparent, and I could figure out which pin (on the bottom) corresponded to which phone plug contact. You might have to enlarge one or two holes in the board, and I bent or broke one unused pin. But the rest of the pins go through the holes to the back of the board, and hold the phone jack in place.

Each switch has four pins (two for each side of the switch contacts). I just pushed them through the holes in the board without any sockets. The pins fit tightly enough so there’s no play after the pins are soldered (as described next).

On the back of the board, there are four wires soldered in place:

One from the “dit” switch to the “tip” contact of the phone jack;

One from the “dah” switch to the “middle ring” contact of the phone jack;

One from the “ground” (outer barrel) contact of the phone jack to the _other side_ of the “dit” switch;

Another from the “ground” contact of the phone jack to the _other side_ of the “dah” switch.

The ceramic fridge magnets (Krazy-glued to the back) are thick enough so that the pins of the switches and phone jack don’t touch the FT-817. I covered the soldered joints with silicone sealant — no possibility for accidental shorts, that way.

That’s it. This was one of the few times that something I built worked right on the first try. This is _not_ a fancy project.

Good luck !