This system works by installing a donor antenna on the roof of a high rise and pointing it at the nearest SF public safety radio tower. I’ve also used a fiber optic backbone on college campuses in the bay area instead of a donor antenna and that accomplishes the same objective.
The donor antenna takes the public safety radio signal and sends it through a coaxial cable to an amplifier that then distributes it throughout a building using omni-directional antennas spread out in the building.
The electrician’s scope includes securely installing the 2″ rigid conduit, installing a weather head (service entrance cap), and pulling the coaxial or fiber cable from the point where the donor antenna will attach to the Bi-Directional Amplifier (BDA).
The donor antenna is provided and installed by the ERRCS company sub-contracted by the electrical contractor.