There is the RRC-Micro PC client, but that is not needed if you have the control unit RRC-1258 with you.
I have been using the RRC-1258 pair using my 857's front panel remotely, but thought when traveling to just take the control unit and use SDR radio on the PC such as Ham Radio Delux (currently have the older free version), leaving the precious front panel at home.
I might be being stupid, but I cannot see any details as to how to configure this, and indeed which SDR or control packages work with RPC1258 and Yeaseu 857D setup. COM2 needs to connect to the PC, and Audio of course, but how to get Ham Radio Delux to connect has defeated me. I am having to use a serial to USB converter; HRD does see the correct COM port. I am sure I am missing a lot.
Thanks
Gerry