Maybe its a state law thing, but we have these tubes today at local bank drive thru and local walgreens pharmacy. They have cameras now of course. I've always

Maybe its a state law thing, but we have these tubes today at local bank drive thru and local walgreens pharmacy. They have cameras now of course. I've always been interested in building a tube into my house for the pure heck of it, because I can. Main problem is I believe PVC pressure rating for compressed air is 0 psi, so there "seem" to be enhanced modern materials that make the job easy, but things aren't as simple as they appear. Also its harder than you'd think to go bidirectional. Unidirectional with simple one way flaps and a timer hooked up to a valve (about a 5 minute arduino project) is pretty simple. Bidirectional is not so simple.