I had a lot of contact with the OCME over the years, even before they were called the OCME.
I don't recall them ever using radios or seeing their employees carrying portable radios. To the best of my knowledge they are dispatched by cell phone, not radio.
Since they don't "patrol" between calls and generally have to return to Albany Street with remains, it makes sense that they don't use a radio system.
All non attended deaths (generally out of hospital deaths) require a call to the office. Information is given to the person who answers the call. After that, the office will call back and state whether the office will accept or decline jurisdiction for the case. If they accept, they will send out a van or occasionally they will allow a funeral home to pick up the deceased. If they decline, the family or whoever is authorized to contact a funeral home and arrange for pick up.