Originally Posted by
mooney
Skipper I'm with you.....how it's been about a year since I've shot PRM's at ATL, and I have done them at several other airports. I couldn't help but notice how much other chatter there was on the monitor frequency each time I shot a PRM there. Like you said it was to the point of not being able to decipher what either freq was saying. So bad I double checked to make sure we had the right freq in monitor. Never had that problem anywhere else. There were normal transmissions on it for other planes. I actually sent a FSR about it.
I may be totally wrong, but I was under the impression that the monitor freq was just a carbon copy of what was transmitted on tower freq. Just like when one guy is up in the tower working local and ground all of his transmissions broadcast over both freqs. So when the local controller transmits it goes out over both tower freq and the monitor freq so that if tower freq transmission is blocked by an aircraft the transmission on monitor remains "unblocked" and readable to the aircraft in the area. Its also my understanding that the monitor (who is in the TRACON) also transmits on both the tower and monitor freq for the same reason.