The referee is NOT in communication with the replay official. The replay official (or his communicator (i.e., assistant)) can page the officials that play should be stopped. At that point, the R goes to the sideline and puts on a headphone and talks with the replay official. Communication that there will be or needs to be a replay is one way, from the booth to the field. Six of the seven officials wear the pager (the BJ does not), and it's not subtle. It will give you a significant jolt. It's not a Taser, but you won't miss the vibration, it will wake you up.
The officials are expected to call the game as if there is no replay to back them up (albeit the slow whistle theory, but that's another discussion). Part of the reason is a practical one: replay can only overturn "obvious" errors. If there is not conclusive evidence to overturn the call, the call on the field stands. Therefore, the on field official had better be calling what he thinks the play is, because unless there is conclusive evidence otherwise, he's right.
What does bother me about the NCAA system is that the R has no say so in the final outcome, and the play is never even discussed with the calling official (unless it happened to be the R).
EXAMPLE: wouldn't it have been a much better methodology if the replay official had actually been on the headphones with the FJ and asked him what he saw? Maybe the replay official would have concentrated on another angle if he knew the decision process which the FJ had gone through to get to that call.
In that way, the NFL system is superior. The R makes the final call, not the replay official, although there is a good bit of discussion between the two during the process. In addition, the R can call over the official involved if need be to clarify an issue.
But in both the NCAA and the NFL, the on-field officials can never instigate a replay by request.
You probably ought not act as spokesman for the entire community. In more than one FCS conference the ruling official is asked to stand nearby, in case the RO needs additional input as to what caused him to rule as he did.
The R is not in electronic communication with anbody, except when he puts on the headset and communicates with the RO. When he does, it is two-way communication, although the RO generally is too busy to be distracted by the R trying to talk to him. Quite often the RO will ask the R to repeat the ruling on the field, so he can verify a) what he needs to be looking at, and b) that it is it reviewable. Often the RO has questions for the R (or the ruling official through the R), and there is nothing improper about that. No, I've never heard of a ruling official say that he thinks he may have missed the call. Rather, he'll simply say that he made the call based on the look he got. While it is true that on-field guys 'generally' rule it as they see it, I know for a fact that, when in question on really tight plays, the philosophy is to rule fumble versus down, TD versus down, catch vs no-catch, etc., because they KNOW that replay can (and almost always will) review it and 'adjust' the ruling accordingly, if needed. That takes some "getting used to" for folks that don't operarte with Replay regularly, but it comes with time.
And, every once in a while, the R will clandestinely initiate a review by announcing that the play is under review - it
has happened - in at least one very high profile game. That is more difficult now, since Rs are to announce the ruling on the field, but still poosible. When the R gets to the headset, he'll let the RO know what he needs to look at. That's why smart Rs will turn away from any cameras, even under routine replays, so their lips can't be read.
As for the pagers, their strength varies, and their 'feelability' depends on the type and somewhat on how you carry them. Dropped in a pants pocket, they may not get felt at all. Clipped on the belt, it is almost always felt. I wouldn't characterize them as giving a 'jolt' - just a strong buzz like a really juiced up cell phone. And who wears them varies by conference and site - as few as four, and as many as all seven (plus sideline replay assistant). When less than 7, Priority should be given to those nearest the transmitting antenna. In some locales, the signal strength isn't enough to activate pagers on the far side of the field. That's not usually an issue at high profile venues, but not every game is at a such locations.
The NFL use of the R as the final authority may, indeed, be better. However, the limited ability of the RO to call for a review is a major source of debate in the NFL. In recognition of that, the NFL ROs ability to call for a review was expanded slightly this year (on scoring plays).
One day, the two will come together.