Reverse-Engineering a Scoreboard Display
hardfault.life
hardfault.life
Here's, for example, a 12 inch 7-segment high single digit for ~$38, including shipping: https://www.aliexpress.us/item/3256802774192337.html
You can use their driver boards, or just scale up a cheap 7-segment driver with a few extra parts to drive the 12v it wants for each segment.
It's not really "programmable", though - the only thing you can set is the duration of the walk/stop cycle, and how long the warning countdown lasts, and iirc it's powered by some pretty high voltages. But nothing is stopping you from connecting to the LEDs directly, via some pins that you can use a ribbon cable to connect to.
Looks like a 1970s military interface. With cards that you overlay on the controller for different sports, but the schools, etc.. lose the cards.
So many operations require strange & confusing sequences of button presses.
At least with basketball professional referees often understand the UI well and can help out in a pinch, but these things are really really hard for volunteers to figure out.
There are some newer ones that are self contained where the computer & scoreboard are integrated and sit on the desk with the scorers and timekeeper. Those have the lovely design that the horn/buzzer is right in the unit and it blows everyone's ears out when it goes off.
Our home rink was built in ~2000 and had a "high tech" system with a palm pilot driving the scoreboard. It got replaced by a computer running a java webserver and internet explorer maybe a decade ago. A lot more friendly for a novice, but the daktronic wired remote switch to start and stop the clock is a lot nicer than having to hit a small click target area. And I could see a skilled operator getting to the point where they could touch type the control box; gotta have eyes on the screen for the web based system (no hotkeys; or at least they're not known by the team parents)
You can still have the web based display and click targets, and have them send the commands to an in-browser terminal/command log. This allows people to learn the CLI while exploring the GUI.
The again the one I want to try actually displays video? So it's probably way harder. I wish I could find more documentation about how daktronics systems work.
You should touch up the joints with external flux.