radioAe6rt

Does anyone know if there are unlicensed HF bands in the US, as there are unlicensed UHF ISM bands where WiFi has bloomed?

Ham operators have been operating on low power (sub 5W) for years. But how cool would it be to open a slice of the HF band to unlicensed low power use, and see what cool services would emerge. Owing to the physics of wave propagation, longer HF radio waves travel further easier than short VHF and UHF waves. HF propagation is also more susceptible to atmospheric conditions, but that’s ok — that’s part of the challenge. We’re talking about 10-80m roughly, which means antenna sizes change relative to the familiar 10cm-ish WiFi antennas. For example, at 10m the antenna needs to be about 15ft long.

To whet the appetite, here is some very cool work done in licensed spectrum in HF digital radio.

Hmm.