For all the GHz-bands I needed a 2m-transceiver and wanted to switch easily between all the bands. I had two FT290 and decided to re-use one as backend transceiver. I kept only the RF main board and added a AVS ATMEGA328 in stead of the Yaesu microcontroller. Now I am flexible in software and hardware.
Using the band switch at the bottom right I can switch the corresponding input from 23 (left) to 24 GHz (right).
Of course the display shows the correct frequency in the selected band.
Recently I added an output after the 2m preamp in the set, to connect to a RTL-stick. Now I can also see the whole spectrum per band on my computer for example a beacon on 23cm: