heaven only knows what kinds of devices they're using at UCLA and other hospitals,
The lesson here is... never say never!
Locally, our guys moved the input freq of the main repeater to the very bottom of 902. What was happening was that so much ISM Part 15 from the hospitals was getting into the input freq of the repeater and creating some very annoying popping noises that resembled a bunch of race horses' hooves on a track. After delving into the band with a spectrum analyzer hooked directly to the repeater antenna, it was shown that the very bottom, close to 902, and the very top, close to 928 was the way to go.....very clean at the band edges. The guys in the NORCAL group had a very similar experience, and suggested this to us.
Similarly, but yet a different matter, are the paging systems that are still used primarily by physicians, so again, hospital areas are a problem. The pagers aren't Part 15, or in 902-928, but they're rock-crushers in power and blast out data (around 930 MHz?) with a vengeance. This will overload front ends of 902-928 radios and repeater receivers, so it's another frustration. Good quality front end filters are the answer in this case.
OK, a little League-bashing from a supporter and Life Member.....they have been way, way behind on this, wrt the 902 band plan. It still includes significant chunks for ATV, which is all but dead, here at least. Too, the 25 MHz offsets, not the 12 MHz offsets implied by the League plan, are what's needed as so many Motorolas, GEs, etc require this. So.....the 902.XXX/927.XXX offsets are no accident, but still not a concept absorbed by the League for some reason. BIG frustration there....WHAT are they doing??
Anyway, just some thoughts. Best of luck in your 33 cm endeavors.