Valentines day is just around the corner and in the spirit of the holiday and to keep myself busy in an attempt to avoid pity-consuming sickening amounts of chocolate whilst listening to Adele, I have constructed a project.

I present to you....the wearable, just-bearable, giant-Teddy-bear-comparable homemade gift for your significant other. A decoration-declaration of undying devotion and moderate technical skill. The latest in flashin' flashion...The Couples Tech-laces.

The Couples Tech-laces are two Perlers worn around the neck (via a beaded necklace) that share the unique ability to beat their hidden "hearts" when put together. Each device is constructed from a combination of Perler beads and basic electronic components.

Step 1: Materials

Note! As mentioned before, for the sake of simplicity I will only be detailing how to make one device. You need to do the exact same thing, with the exact same materials for the companion device, the only difference is the design on the front, and which side you glue the battery pack and switch.

You will need:

Conductive Metal (I used metal buttons that I cut up, it needs to be able to be cut by scissors)
Wires
Red LED (I got all my electronic components from the handy Analog Parts kit)
Popsicle Sticks
Perler beads and board (if you don't already own these its cheapest to buy as kit from your nearest craft store/online)
A clear plastic spoon/fork/knife
Ironing surface and iron
Hot Glue
Needle nose pliers
Triple A battery pack

Step 2: Design the Perler

This is arguably the trickiest part. Select a version of your friends name, or a nickname ( I used their spirit animals, a Raccoon and a Panda) that is less than five letters or so. Then write them down and try to see if there is a place in the name that you can "hide" a heart shape in the negative space. A good place if you are stuck is to put it inside letters like A, O, U, W, V, or between letters.

The heart does not need to be too "hidden". Most people are not going to notice it because they are not expecting it.

Once you have designed the Perler go ahead and put it on the bead board. Then iron it. DO NOT put beads in the negative space you are designating for the heart. If you have never done a Perler before detailed instructions can be found here.

Step 3: Attach the Electronics

The circuit is simple, being that it is just a battery connected to an led with a break (in the circuit) placed near the right or left side of the Perler. On one device it should be the right side and the other it should be the left (front-facing for both) but it doesn't matter which is which. The break should be simply two exposed wires, one from the positive side of the battery pack and one from the positive LED lead.

Actually building this onto the back of the Perlers tends to be the more difficult part. First, hot glue the battery pack onto the side of the Perler you intend to place the break in the circuit (the break will later become the contact switch). So again, it doesn't matter which side as long as the battery packs are glued on opposite sides for each Perler. Then using Popsicle stick and hot glue, mount the led so that it is parallel with the top edge of the battery pack (about a half and inch from the beads). This will help with the diffusion of the light. Finally, take your clear plastic silverware and break off the handle. Hot glue it across the back of the heart space so that the light is diffused further.

Step 4: Make the Custom Switch

The main idea behind this project is that it is only operable when the two of you are together. To maintain this, I am using contact switches instead of push button, that way the only practical way that you can make the hearts "beat" is if they are pressed against each other. To do this, I used the conductive metal to make two bottom leads (each connected to one of the exposed wires on the devices circuit) and one top panel of metal to trigger the companion device simultaneously. Use the needle nose pliers to squeeze the metal over the wire to ensure a snug connection.

You do not have to wire anything to the top metal panel, it serves only to conduct and complete the opposite devices circuit.

Step 5: Operate!

To wear, simply attach to a beaded necklace. To operate, place the contact switches face to face (so that the two leads are facing the opposite devices metal panel and press firmly together. If you are having trouble check your connections and make sure that you are making enough contact!

Step 6: Extensions Ideas

If you are looking for where next to go with this project, it would be interesting to add a microcontroller, an LED strip and additional contact strips (instead of one trigger strip and one set of leads maybe multiple trigger strips nad multiple sets of leads) so that different devices placed together produced different results! For example, making it so the hearts beat when your with your significant other, but making the device play a tune when matched up with... say your best friend.