Bomb deployment siren in MvM

[Jacov]

Hi. On other MvM maps, when bomb carriers nearing the bomb hatch, the siren plays repeatedly.
I don't have this in my map, and I'm not sure how to do it properly.
I decompiled a bunch of maps and still can't find anything related to this. Is this just an ambient_generic?

Can someone please help?

 

[Scatter]

Hello! I believe this is just as simple as setting a trigger brush as an entity called "func_flagdetectionzone", as pictured below:

You'll want the trigger to cover the area where you want the alarm to go off.

It also has this output, which I believe handles the stopping and starting of the alarm, but I'm not too sure. I think I just ripped it from a valve map and it worked.

I can't test it at the moment, but this is how one of my old non-functioning maps uses it. Hope this helps!

 

[Jacov]

Thank you!