In what little is available online about the SR2000A I have read that you can set the FFT search to -99dbm as the weakest signal it will detect. I am wondering just how strong of a signal AOR's calibration is calling -99dbm? I guess my fear would be the need for a "S-9" signal to register with the FFT search. Not sure what one could relate it too but another receivers S meter. Any notable experience you have had with comparison weak signals that will register with the Sr2000's FFT as compared to another receivers common S meter reading? Range of interest would be the 225-400MHz range...The SR2000A is definitely not like the SDU5600 and is a very good receiver. While it is not perfect it certainly will change the way you look for active freqs in your area. I use the fft search for the 225-400 range and it works fantastic. You may miss a few weak transmissions but that is the nature of fft. It is the quickest way to search a wide swath of frequencies for action.
Watch this vid to see an SR2000A in action.
AOR AR-Alpha Review Problems & Faults #3 - YouTube
Jody, I had the SDU5600 for a while, which is the same idea minus the built-in receiver. It did a very poor job with weak signals. I returned it.