Chocolate?
Paul has talked about using hot glue to hold the circuit to a ‘chocolate block’, but I’m not sure if that’s the same as the European style connectors we can get from Radio Shack. I did manage to find dark colored versions of them in a Google search, but the only color I’ve ever seen is white. I use them on various projects by cutting off a few of the twelve position version.
Dead CFL Lights
CFL lights usually have a small toroid core that can be removed and rewound with heavier wire. The ones I’ve obtained make decent JT coils.
Also, the CFL usually has a choke that’s a round cylinder with two radial leads (coming out one end). You can use this by winding a second winding on top of the shrink tube covering. Just add some black electrical tape, glue or clear nail polish to hold it in place. Even regular adhesive tape will hold the wires.
Mickey Mouse
There is another way of using two of these chokes side-by-side to make a coil. The ones in my earlier blog are axial, the a single lead comes out of each end, but the radial chokes (leads both come out of the same end) should work similarly. I have never seen any commercially made product use this method, and in my opinion it’s a Mickey Mouse way of doing it, but it works.
Don’t forget that you can get some cores from mouse cords, keyboard cords and keyboards. Any cable that has a plastic bulge close to the connector has a potential core. You may have to cut off the cable and plastic, but it’s usually a core that’s good for a JT – maybe bigger than you want but will handle larger wire. I said ‘and keyboards’ because there may be one or two cores on the wiring inside of the keyboard, so you’ll have to open it up to find out. These cores are in the 6 to 10 mm size range, an ideal size for a JT. Just make sure you put the unwanted circuit board in the e-waste pile until you accumulate enough to take to the recycler. Some waste disposal companies will do e-waste pickup at the curbside if you call them to schedule a pickup.