All paramedics service in LA County are from fire depts. The ambulance companies are only EMT. So any comms with hospitals will be from fire. The only exceptions would be Mercy Air who has flight nurses and LASD'S Air-5 which has paramedics deputies on board. On some busy weekends they have a trauma surgeon on board who also happens to be a reserve deputy.
In the past 5 years I'be never seen LACOFD Paramedics use a radio, its always been by phone.
Not exactly true. There are many private ambulance companies, the largest being American Medical Response (which does contract with many fire departments, including Ventura County Fire), and they DO empty Paramedics, in addition to EMTs. So to say that “All paramedics service in LA County are from fire depts. The ambulance companies are only EMT” is not an accurate statement.
As for your comment on “Air-5”, I was a patient on that about 20 years ago. One of the crew was an Orthopedic Surgeon. Good thing, as my injury was a shoulder dislocation.