if you want to learn about shortwave and some longerwaves, the business of latency arbitrage, massive receive arrays, over-horizon radar (Duga), how data transmission is related to over-the-horizon radars, why AC grid sync distance is limited by wavelength of 50Hz ...
I built the first microwave network ny-chi (as in "Flash Boys"), AMA within NDA. or without, if you catch me at milliways' whiskeyleaks afterward. @apilosov on Twitter or matrix