When 2 sectors are combined, do they use 1 frequency? Or does the controller monitor/control on 2 separate frequencies? I have read blog posts by controllers who complain that they have "2 airplanes calling up at the same time on the 2 separate frequencies." But I also know from other posts and visiting facilities that they often use just one frequency for combined sectors.
Any clarification would be appreciated.
I'd rather have someone working at a TRACON answer this, as they will have it absolutely correct, but from my observations, here's how it goes.
When I'm at KLAS, and they combine all their Approach/Departure frequencies (that's about 5 approach and 4 departure) on 125.02 (or where ever they want them all combined), they still transmit on the other frequencies. so I could tune to one of their other frequencies (say, 125.9), and still hear the controller, but not the pilots. So yes, it is possible that 2 separate pilots can call the controller at the same time on two separate frequencies.
Prime example. 125.02 is combined for all of Las Vegas, yet in KVGT's ATIS they specify to call Las Vegas Approach on 133.95 if in the air, or 124.0 on the ground. When that happens, they generally ask the pilot to "change to my frequency 125.02." (see FAA JO 7110.65, 2-1-17.d)
Again, someone here who works at a TRACON can explain what they do better, but this is the jist of it.
BL.