Radar is a useful tool with familiar uses such as detecting aircraft and observing weather. It also has some less known applications, such as a technology known as ground-penetrating radar (GPR).

One of the most interesting is [Glenn Powers]’ Open Ground Penetrating Radar. It’s exactly what the title says: an open-source radar system that can see into the Earth for less than $500.

Antennas used with ground penetrating radar (GPR) come in different shapes and sizes. The largest antennas typically radiate the lower frequencies necessary to detect the deepest targets.