On 10/31/2022 at 8:37 AM, neutrino said:
Perhaps try a loopstick antenna instead?
The radio waves consist of electro-magnetic waves. And if the electrical waves are really long then it might be more practical to utilize a loopstick antenna to use the magnetic part instead for better coupling to the wave.
https://en.wikipedia.org/wiki/Loop_antenna#AM_broadcast_receiving_antennas 
Loop antennas or "bar antennas" used on portable AM radios are nowhere near as efficient as long wire antenna. I've been a ham for a bit now, and I can tell you firsthand, that an outdoor dipole at 1/2 the wavelength of the transmitting station does a much better job receiving a signal than a loop or compromise antenna.
On 10/30/2022 at 11:10 AM, Travis Bryant moore said:
Well I do live near the Appalachian mountains. Maybe my body was a 2nd ground. My antenna was around 30ft long. Aldo found this.
http://www.arrl.org/files/file/Technology/tis/info/pdf/culter.pdf
Your body acting as the ground is a super common occurrence when an antenna system is not balanced (ie: has at least as much ground plane as radiator, for verticals, or has an equal length negative pole for horizontals.)
In the case of crystal radios, where you're trying to pick up AM broadcast or shortwave signals, you usually want a horizontal antenna, and some sort of grounding system.
As to the mystery radio: I'm unclear what you are trying to do. The "mystery" radio is just a crystal set without a ground. A transistor radio is not a crystal radio, since crystal radios don't use batteries or transistors. If you're asking whether a transistor radio can effectively operate with a long wire, ungrounded antenna system: yes it can. I have done so, to good effect. You never want to
transmit with an untuned, ungrounded long wire, but for listening to broadcasts, you can basically just connect any long piece of wire to an AM receiver and go crazy, extending it until you get a clear signal of whatever you're trying to listen to. Personally, I have a wire strung around the sunshade on the deck outside my room... I ran coax out through the wall, then ran the center along the beams. It does a good job of picking up all the local radio stations, although not so much with things like WWV (mostly because I'm surrounded by mountains on 3 sides.)
