I've not seen any love here at the site for crystal radio sets. Before you roll your eyes, crystal radios were THE only radio most folks had, and were considered good enough for both the Navy and Army - for WWI. Many use no power, offer fantastic selectivity and sensitivity (compared to some of the cheap Chinese crank 'sw' radios). Some radio kits offer audio amplifiers vice RF amps. The same applies, more technical kits offer both RF and audio amplifiers. NONE have so-called local-oscillators (LO). A LO emits measurable RF energy and can be detected and DF'd. For the truly paranoid, crystal sets offer an opportunity to have a sophisticated receiver - covering AM and short wave that is 'dead' -- something that emits no energy. On the other hand, you can build a crystal set - yourself -from junk or from a kit, learn a bit about tuned circuits and radio in the process. So? So, here are some links that offer both finished radios, and kits that go from simple to wild. Couple of years back when my son was in the Cubs, we took a den out out the desert and gather all the needed materials for a radio (except headphones) from wire & diode (busted TV) wooden base (orange crate) coil forms (PVC pipe). Each made a working radio in two sessions. SO - if you have kids, grand kids or just want to have fun, check out these inks. Kits THE DUNWOODY HIGH PERFORMANCE CRYSTAL RADIO KIT!! (AM thru 12 Mhz) Borden Radio Company - Radio Kits and Designs for Old and New Styles For the DIY type with some background https://antiqueradio.org/econoceanic.htm (DIY radio) From junk The Creative Science Centre - by Dr Jonathan P. Hare Examples of what can be done with a bit of time and care Dave's Homemade Crystal Radios Main Page. Ready made radios Shortwave Crystal Radio Receiver Kits can run from 8 to 10 USD all the way to 100S of USD. IF you are looking to combine your woodworking,metal, and radio skils, this is one way to have fun. SO or You get to chose. Have fun.