From the beginning I wanted to see the band activity on a waterfall diagram on my laptop's screen.
For that I use an SDR Dongle (in my case a MSI SDR) which is connected to an IFace adapter card. This adapter card is connected to the IF of my FT 991a (many other transceivers are also supported and someone who is at least a bit into electronic and soldering can build it into a transceiver within some minutes). The SDR Dongle is furthermore connected to the Raspberry by a normal USB Cable. The Raspberry as my remote server has rsp_tcp installed which is an SDR-Server.
I start the rsp_tcp server by adding the following two lines into the rc.local. It's neccessary to start the rcp_tcp server with a delay of 20 Seconds since it didn't wanna start directly - but with the delay it works just fine.
/usr/local/bin/rsp_tcp -a 192.168.125.9)
Now the server should run and you should be able to connect to it from SDR Console or HDSDR and others. Normally theese programs work with SDR Dongles connected to local USB ports. Since we wanna use it remotely we need a driver DLL file which pretends the rcp_tcp is a local SDR dongle. So just download ExtIO_RTL_TCP.dll from https://github.com/hayguen/extio_rtl_tcp/releases and copy the file into the root directory of the SDR program. The following settings work fine for me:
In addition I use OmniRig to synchronize the used frequency and the mode with my fransceiver. The setup is very easy as you can see in this demo video.
The way of connecting the SDR dongle to a commercial USB Device Server is not such a good idea. Initially I tried that but it ran very instable.