It’s an SDR transceiver for HF which does all the work of quadrature splitting and mixing with homebrewed modules rather than the more usual technique of hiding it in an SDR chip. It’s a very ...

(Embedded below.) The video covers LimeSDR, HackRF, and the Pluto SDR, although the amplifiers should work with any transmitter. The SPF5189Z module is quite cheap and covers 50 MHz to 4 GHz ...