You can also go very long distances if you use forward-error-correcting protocols like JT9 or WSPR.

WSPRNet[0] is a network of WSPR transceivers that use milliwatts to communicate across the world. It's just.... very slow.

Edit: And this is very frequency dependent.

[0] - http://wsprnet.org/drupal/

Yeah, I've been wanting to try JT9 but haven't picked up a HF radio yet. Some of the moon bounce stuff is just incredible.

Might just be me, but I read this as ~2 kilometers, rather than the intended ~2,000 miles.

Haha good catch fixed that, meant 2,000 miles.

FWIW, the referenced article describes it more conventionally:

> The distance was 3,089 kilometers (approximately 1,915 miles)

Using ARPS when I helped launch a weather balloon while in college, we were recorded by a station in Las Vegas. We launched south of Phoenix so at least 300 miles.

We were transmitting at 3 watt using a small Yaesu hand-held connected to a micro-controller.

Could this be replicated on an imaginary pure flat land ?