This video shows you step by step on how to make a simple Survival Crystal Radio without batteries or electricity used. No special tools or skills needed. Most parts can be had from recycled things. The purchased parts run about $3. Good during power failures, when batteries are not available, for prepping and similar.The radio picks up the standard AM broadcast band. Approximately 535 to 1700 kHz.You can make that more or less with the coil design.