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This is the first radio I built. I was about twelve. The parts came out of old tube TVs: a small 0.67 mH choke and a 1N87 germanium diode. I mounted them on a scrap of cardboard and slid the cardboard into a discarded pill bottle. The earpiece is a crystal (piezo) unit. There is no tuning capacitor. The choke and the diode were the whole circuit, so it locked onto one strong AM station - in Salt Lake that was almost certainly KSL. I still have it.
I took it to church and sat on the front row. Sitting there gave me access to the metal strip that edged the carpet. I clipped onto that strip and used it as an antenna. The other boys next to me got a turn with the earpiece. A pill bottle and a piece of TV salvage were enough to pull a station out of the air. That was the point.
A classic crystal set is coil, capacitor, detector, phones. This one skipped the capacitor. The choke was the inductance. The 1N87 (germanium, DO-7 glass) did the job a galena whisker did on the 1920s board. A crystal earpiece is high impedance, so it works without a transformer. One strong local carrier was all the selectivity you got. That was enough.
I have kept the little radio I built in the plastic bottle as a reminder of where it all started. Salvaged parts from discarded TVs made a circuit that magically plucked a radio wave from the air and delivered it to my ear. The mahogany E.I. Co. set on the other page is the 1920s version of the same idea. This is the 1960s-70s kid version: TV junk, a pill bottle, and KSL on the front row. The path from this bottle to designing and building my own 8008 computer was a quantum leap at that time. From that experience I became enamored with the idea that I could receive radio waves traveling around the world. Not too many years after that I earned my Novice license and started producing my own radio waves for others to receive.