I stumbled across this video while watching YouTube videos. He doesn't spell it out in the video explicitly but this phased array system covers 4.9 to 6 GHz. It looks like he's shooting for a price range of $50-$100 for the 4 -cell board (minus the Raspberry PI), and his 60 board EME array (mentioned at the end of the video) would cost $2.5k-$5K. I'm a bit skeptical that you can get EME to work with just 240W of transmit power, but maybe with enough signal processing??