Yes you can control the SBITX from the laptop quite easily but you need a wifi/ethernet network. I use JTDX installed on the sbitx directly because I prefer it over WSJT-X. With the work I am doing on the sbitx at the moment I use VNC all the time and have used JTDX on the sbitx via iPad and Laptop many times with this approach. Checkout the sbitx facebook group.
Remember that basically the sbitx is a computer with a radio capability, the raspberry pi is a very capable device and as a computer it can do all the radio stuff you want remembering that there is only finite resources, the stock pi 4 used only has 2GB of RAM and I have brought it to slow crawl trying to run too much on it at once, but JTDX, the SBITX app and a browser for pskreporter has run fine on it. I upgraded mine to an 8GB pi4 but you don't need to if you take care with what you try to do with it.
Doesn't matter where you are, if you carry a modern mobile phone around with you, you already have a personal wifi hotspot, doesn't matter whether you have a 4g signal or not really but it is useful for pskreporter access etc.?
If that doesn't work, connect laptop and sbitx together using an RJ45 network cable, may need a usb - ethernet adaptor for laptop depending on make as some don't have ethernet ports on, to use this direct approach you will need to configure the sbitx and laptop network ports to fixed IP address instead of using DHCP e.g. Laptop as 192.168.0.10/24 and the sbitx as 192.168.0.11/24. this choice is deliberate as many devices use the lower numbers for specific uses e.g. 192.168.0.1 is usually the router, the /24 on the end is the subnet mask, sometimes represented as 255.255.255.0 if you have to enter it in this way in the config.
That is the network setup sorted and to prove it, go to a command line on the laptop and type ping 192.168.0.11 and you should see a response from the sbitx, from the Terminal window in the sbitx type ping 192.168.0.10 and you should see a response from laptop, that proves your network connectivity is good assuming you get a the responses of course. if you don't you may need either a crossover RJ45 ethernet cable, not all ports autodetect connectivity, or use a little portable ethernet switch that can be self powered or powered from your power supply feeding the sbitx.
Now for the config bit to get going, assuming you have wsjt-x configured on the sbitx or other digital s/w.
if you didn't already when you got it, you will need to setup the VNC server on the sbitx, open Terminal window and type sudo raspi-config and press enter?
from the menu, select option 3 - Interface options, then select I2 - VNC, select Yes at the prompt, wait a little then click OK, you will be returned to main menu,?
I would recommend before leaving the raspi-config main menu, that you visit the display options choice and set the VNC resolution(D3) to something more comfortable for what you are trying to achieve. That will make the remote desktop better from a resolution perspective for the software you want to use within the sbitx.
Select Finish from the main menu and then Yes to the reboot.
On your laptop, download RealVNC client for your OS version, there is one for Windows, Linux and Mac, install it and then setup the connection to your sbitx via the client, you will see an icon in the sbitx top menu bar on the right indicating that VNC is running, if this is running then you should be able to connect from your laptop to it using the RealVNC client. To configure the client, you will need the IP address of the sbitx as configured earlier, your username and password if it is different from the defaults it came with. When connectivity is first established you will see a pop-up showing some detailed info and asking if you want to continue, clearly the answer is yes to this, you will then be shown the sbitx desktop that can be resized to suit your taste by dragging a corner of the window to resize it.?
That is a shortened version of how to connect and operate the sbitx using VNC remotely.
I was using VNC to help jog my memory for the steps while writing this reply, it is the best method you can use for what you want to achieve.
As for trying to use digital radio software on your laptop, using the built in hamlib server on the sbitx and with the wifi/ethernet connectivity described above it may be possible though I haven't tried it as I want the sbitx to be self contained and maybe use an iPad via VNC to control the sbitx which I know does work with the approach described and had a few FT8 contacts in this way when out in the Motorhome, but I like a real keyboard so the laptop and VNC is my go to for 90% of the time at the moment.
Just to comment on one of the other options, not done this with the sbitx but another pi that I have, I have used a usb-hdmi video capture card on a 10" android tablet to connect the pi and it does work, but its not great, so laptop or tablet with VNC is by far the best approach, my laptop snip of sbitx desktop via VNC, I am running 64-bit os on the pi hence the difference from the stock desktop:
Regards
Paul G0KAO
