I read this post on the RTL-SDR website for a Up/Down Converter board that shows 0-6 Ghz but
maybe capable of up to 13 Ghz and thought I would post it.
https://www.rtl-sdr.com/testing-the-electrosense-up-downconverter-expansion-board-for-0-6-ghz/
Info on the ElectroSense Project site.
https://electrosense.org/#!/
Mike
N6IMF