MIAMI — Can you hear me? Can you hear me now?

The all-too-familiar cell phone refrain can now be heard on NFL fields every Sunday, as defensive coaches this season were given the go-ahead to radio calls into their players' helmets. Quarterbacks have had speakers in their helmets since 1994, and now, for the first time in league history, selected linebackers and safeties enjoy the same benefit.

Channing Crowder and Akin Ayodele are the Dolphins linebackers designated to wear the radio-equipped helmets. Only one can wear a live helmet at a time. It has a green dot on the back so nobody gets confused, and the backup radio helmets stay closely guarded on the sideline. Crowder, the primary wearer of the transmitter, admits he was "startled" the first few times he heard defensive coordinator Paul Pasqualoni barking, "Watch the bootleg! Watch the pass!" in his ear. He said there has been the occasional crackling noise after bone-crushing hits, but overall, he and Ayodele give the system rave reviews.

They say it is a speedier — and more tamper-proof — system than deciphering hand signals from the crowded sideline. And, they feel they finally have a prayer against those hurry-up offenses.

"Defenders have been screaming at us for years that the offense gets all the advantages, that all we cared about was scoring points, so this is our way of leveling the playing field," said Ray Anderson, the NFL executive vice president of football operations. "Seven weeks in, we've had very positive feedback."

HIGH-TECH WIZARDRY

Each of the league's 32 teams paid $28,000 for the high-tech communication system, which uses 268 million military-grade encryption codes to protect the frequencies from hackers. Yes, this is serious stuff. It is so serious that the NFL deploys a five-person crew to every game specifically to deal with the radio helmets.

One official's job is to control the clock and man the radio on-off switch. He activates it when the 40-second play clock begins and shuts it off at the 15-second mark, or when the ball is snapped, whichever comes first. Two "frequency troubleshooters" — freelance electronics experts — man the sidelines and are on hand to fix communication breakdowns.

And then there are two security guards whose job it is to watch over the 3-by-4-foot black trunks that house the backup radio helmets on each sideline. The trunks are decorated with a lime-green helmet with a lightning bolt through it, sit near the Motorola truck, and they are off limits to non-designated players, coaches and team personnel.

After each game, the radio helmet crew submits a report to the league that details the usage of the helmets, and the return of the equipment and the spare battery packs.

"We have to guard the integrity of the process," Anderson explained. "The security of the system is at a very, very high level, and we are confident it is virtually foolproof."

The NFL voted by a 25-7 margin in April to institute coach-to-defense radio helmets. The equipment rule, which was the most significant off-season change this year, had been voted down in 2007, but the New England Patriots' "Spygate" controversy heated up the issue.

The Patriots admitted illegally videotaping opposing teams' hand signals, and the NFL came down hard with a $500,000 fine for Coach Bill Belichick, a $250,000 fine for the team, and the loss of a first-round draft pick.

When the season began, the Patriots were the only team to say it didn't intend to use the coach-to-defense radio helmets, but Anderson said all 32 teams have now used it and other than occasional glitches, they have had no complaints.

"We feel it was a very, very prudent investment because it is advancing the game and leveling the playing field for our defenders," Anderson said.

DOLPHINS APPROVE

It certainly has the Dolphins' stamp of approval.

"It definitely helps our defense," Crowder said. "The offenses try to run people in and trick the defense, and now we can make adjustments faster. It puts the defense on an even keel with offense for the first time. Two years ago when they first started talking about it, I thought, 'This will never happen.' I know fans like to see points going up, so I figured the NFL wouldn't make this move, but I was wrong. The Patriots started cheating, so we got our radios."

Ayodele said the radio transmitter allows coaches to give him much more detailed information than a hand signal can, and that has proven helpful. A coach can instruct him to shift direction or tell him to inform a teammate about a nuance of an opponent's habits.

"The first couple of times I jumped because I wasn't used to hearing voices in my head," Ayodele said. "It was like, 'Is someone talking to me?' But I've gotten more used to it. It's so much quicker and smoother to hear the call and simultaneously be able to tell our teammates as we go up to the line. The only problem has been sometimes it's too loud and I have to turn it down."

Crowder joked that Pasqualoni "is an excitable" guy, especially after defensive breakdowns, and sometimes has to be reminded to turn off his microphone.

FEW DIFFICULTIES

"All of a sudden, I'll hear, Ar! Ar! Ar! Like a dog barking. Really loud. And it's Coach P, with the mike hanging off the headset, yelling everything that comes to his mind. Sometimes Coach George Edwards, the linebackers coach, has to calm him down, and if I still don't understand what Coach P is saying, Coach Edwards will send a hand signal out to me, the old-fashioned way."

Pasqualoni said he was "apprehensive" when he first heard he'd be sending radio instructions to his players, but he has grown to love the system.

"It's been working very well for us," he said. "We have no real issues with it. One week the battery went out, so we didn't have it for a few plays, but other than that, it's been great. I can get guys the call so much quicker and easier this way. I just have to remember to push that little button down, and remember that there's a short delay so I don't send the call in mid-sentence."

Pasqualoni agreed that the newfangled helmets are shifting the league's balance of power. Since the quarterbacks have had coaches in their ear, scoring and completion percentages have increased, and this new rule may wind up reducing scoring.

"It's still too early to tell what this will mean for the NFL long-range, but our intent was to even things out for the defense," Anderson said. "Scoring had gone up, and you'd have to think this will help the defenders keep up with the no-huddle offenses and critical third-down situations."

The most cumbersome aspect of the new rule is the sideline wardrobe changes. Because only one defender per team can wear a live-wired helmet at a time, teams sometimes have to do some quick shuffling on third downs, when a radio-helmetted player gets injured, or when there's a radio malfunction.

"It is an electronic device, and if you hit somebody real hard, especially helmet-to-helmet, it'll cut off for a while and start crackling," Crowder said. "That has happened to me a few times, where the speaker gets dislodged after a big hit. But I just went off the field, gave my helmet to the technician, and he fixed the wiring. One time I was hearing our offense's radio signals in my helmet, kind of like when you hear someone else's conversation on your cell phone, and the technicians crazy. This is serious business."