I once was in need of a random-wire tuner and just didn’t feel like buying one. I knew I would rarely use it… so I built one from junk parts. I had the air variable capacitor and some SO-239 connectors. For the box I just used a metal watch case I found at Good Will for $.50. By the way, Good Will is an awesome place to get metal cases. The coil is just a wrap of 22g magnet wire around a 35mm film canister. The switch is a 12 position rotary contact switch I purchased from a local electronics place. Does it work… YEP! It can tune most random lengths of wire from from 40M to 10M. I have a video of the one time I used it while in Hawaii (Click To Watch on YouTube).