Several years ago I bought a remote antenna switch board from Sweden, built it, but never added a control box or actually used it. With an increasing interest in remote operating, the idea of being able to switch antennas when away from home sparked renewed interest in the antenna switch I built some years earlier. On the web there are quite a few Raspberry Pi projects that use relays, there was even an amateur remote antenna relay project. However the available code was either plain awful, or not really suitable.

Thanks to the availability of free AI assistance, I was able to produce a working Python script in a few minutes that really worked and was web enabled, something as a novice programmer I would have struggled with. As well as being useable with a desktop PC, it also displays very nicely on a mobile phone as shown below.

The parts needed are as follows:

An antenna switch, this one from Sweden is pretty good, handles 1500W, and is an easy project to build, although you could use any similar remote antenna switch.

A Raspberry Pi and mains power adapter for it, I used a model 3B+ which has built in WiFi, you do not need any particular model and no point in spending a lot for one. Add a 32 GB SD card to go with it. The 3B+ has a 64 bit processor.

A 12V power supply for the remote antenna switch, the relays on the above board only draw about 30 mA, so almost any electrically quiet "wall wart" PSU will suffice.

A relay "HAT", or board, for a Raspberry Pi, I used a board from Amazon UK, it was an SB Components item described as PiRelay 6. You could use any similar board, it does not need to have 6 relays, but one with 6 will match the Swedish remote antenna switch. The current Amazon UK item number is B09FLK57G2

I use the Raspberry Pi in a corner of the house that is closest to the outside antennas, it connects to the internet via WiFi to my router. I have a multi-core cable running to the outdoor antenna switch. The cable i used is outdoor grade CAT 6 Ethernet cable, together with matching waterproof RJ45 coupler and indoor RJ45 patch cable and wall mounted "network" socket. Using Ethernet cable is both easy and low cost. The outdoor junction box has silicone grease on the plugs/sockets to avoid condensation damage to the contacts. A suitable Ethernet outdoor cable junction box is Amazon UK item B07G34M63G, siicone grease is Amazon UK item B0058223PU

Programming a Raspberry Pi is well covered on the web, I used the latest 64 bit operating system. Raspberry Pi imager will automatically install the Pi operating system software on your SD card, together with your WiFi settings and enable SSH. For those unfamiliar with Linux and Raspberry Pi use, you can remotely access your Pi without needing a screen and keyboard on the Pi, you use SSH from a command prompt on your home PC.

The antenna switch Python script uses port 5002, access it from your web browser as 192.168.xx.xx:5002 (or whatever web address your network uses) edit the port used by the Pi in the Python script if that is a problem. When a relay is selected, all other relays are turned off, pretty much as you would expect it to work.

You can edit the Python script to change the text as to which antenna is connected to which relay, etc, by using the free Windows program Notepad++

I cannot offer much support on how to configure a network for remote access, or how to configure a Raspberry Pi to boot up running a Python script, details are easily found on the web, you might even ask ChatGPT. For my remote access I use Tailscale, which creates a secure network with fixed IP addresses and even works over cellular with CGNAT. Tailscale is free for home users. A single line command via SSH is all that is needed to setup a Raspberry Pi to work on a Tailscale network, all the info is on the Tailscale web site.

Links

Antenna switch board
Raspberry Pi imager
My Python script