Original Message

I don't know why some hospitals use 123.05 instead of 123.025 but can only speculate That maybe the hospital that's insists on frequency 123.05 is the major trauma center in the area. With other hospitals in the general vicinity.

that may be the hospital that's insists on frequency 123.05 is the major trauma center in the area. With other hospitals in the general vicinity.

If the major trauma center is a busy hospital, it would Somewhat deconflict Traffic between the major trauma center and the outlying hospitals. And as mentioned, it's likely that helipad lights are controlled by the frequency.