CW Key
This is a simple straight key I built from scratch. I already had a straight key, but thought it would be fun to try to build one. I'm no machinist and don't have the tools to make one from metal, but I decided to try to build one anyway. Instead of machining the key lever and mounting it in a base, I decided to try to use the springiness of a flat piece of metal to act as a key lever.
I had some wood on hand which was left over from a home construction project, so it was easy to make the base for the key. The base consists of part of a 1X4 which was already cut to about 2 inches wide. I put a bevel on one end of it, and to the other end I attached a 1/2" thick piece of board to mount the lever to. This raised section allows for movement of the key lever. I sanded down the key base and then stained it with wood stain. Once this cured I spray painted the entire base with clear spray paint to give it a glossy finish.
The lever itself was made from a blank used to fill empty slot holes in the back of a computer. The key knob is a drawer pull knob salvaged from some old kitchen cabinets. A screw secured with two nuts serves as a contact, and the lever is secured to the wooden base by the means of two screws. A shiny 2004 penny serves as the second contact, with a wire soldered to the back which was inserted through a hole drilled through the base, then the penny was glued down. A trough was routed in the bottom of the wooden base through which the wire runs toward the back of the key.
At first I had planned on mounting two binding posts on the rear of the key for connection to a cable. These are the posts used on power supplies & other test equipment used to connect wires. However I only had one of the type of post that I wanted to use. While looking for either a second matching binding post or a set that would work, I came up with the idea of using an RCA jack. My CW keyer uses an RCA jack, so I could use the same cable for both the keyer & straight key.
I happened to have a couple of RCA jacks on hand which are panel mount jacks. They have screw threads on the rear and use large nuts to secure them to a panel. I decided to use one of these, since I could drill a hole only slightly smaller than the diameter of the jack's threads. I drilled the hole in the rear of the key base, and once that was done drilled a smaller hole through the bottom into the larger hole so I could thread the wire soldered to the penny. I then soldered this wire to the tab on the center conductor of the RCA jack and screwed the jack into the wood. I made sure to include the tab ring around the jack which makes contact with the key lever, thereby completing the circuit.
Overall the key was very easy to build. It works quite well also, though at first I didn't think the lever had enough spring to it. It does, though, faithfully raise the contact off the penny when I let off the key. The beveled end of the board allows the wieght of your hand to hold the key in place so that it is not sliding around the desk while being used. Since the key was made from scap parts laying around, it didn't cost me anything to build it, except for one cent for the bottom contact.