Okay so place two sentries, a button and a checker.
Make one on your team and one that is not on your team.
The sentry that’s on your team is inactive on game start
Wire the Button to a Checker.
Button Pressed > Run Check
Wire the Checker to the Sentries.
Check Passes > Deactivate Sentry Not on your team
Check Passes > Activate Sentry On Your Team
Did it work, @anon77744531?
Don’t forget to mark a solution if it worked!