The dead period in college football is, basically, what it says. What it is is a time when college coaches aren't allowed to contact you. They can make some phone calls, but it is what it is. It's to slow the period down. Let the college coaches take a little bit of a break. Let the athletes take a little bit of a break.
Usually, that dead period will come around with the coaches' conventions. That dead period will be around signing day when they want coaches to be in their office and not out looking at you.
When dead period comes around, it's when they can't be off campus, evaluating. They can't be having a contact in the contact period. They have to stay home. In fact, you can't even visit them during a dead period. They can't have contact with you other than brief phone calls. Those are also mandated by the NCAA, how many you can have and when you can have them.
The other dead period I think is important to mention is around the holidays, around the Christmas vacations. It usually starts until about mid-December, and then will go all the way through until the first weekend in January when you can then start having official visits again.
That's what the dead period is, trying to slow everything down.