Performed some telluric (through-the-earth) communication tests with colleage Griffin Brock a couple hundred miles away with a Tesla Coil.

To maximize conductivity I just tossed a big ground strap into the ocean to use the Earth as my ‘antenna’. Worked surprisingly well, could pick up AM radio stations all over.

It was quiet and sporatic, but we were able to confirm signal reception >200 miles away around 7mhz with 60-100 watts.

It’s a neat first start to some higher-level experiments to measure propagation speed of longitudinal waves through-the-earth. Based on Tesla and Dollard’s notes, velocity should be around 1.53c

A big lesson-learned here though is that I need a really good ground to continue doing telluric experiments.

Since the shop is probably only 10-30ft above sea level, I think I am going to end up trying to ‘bore’ a hole straight down to the water table and use that as my ground conductor.

It’s going to be quite the engineering process though, to find a way to bore a 20-50ft hole using off-the-shelf hardware. Knowing my luck it’s mostly rock, so definitely need a core bit (or several) Probably something like a 2×4-based gantry frame, a big pile of 5/8″ threaded rod, some core bits, a pump and filter, and patience.