Hytera S series intercom

S1 intercom realizes two-group standby communication through two PTT buttons. Taking the hotel scene as an example, the side PTT is the hotel's overall intercom button, and the front PTT is the intercom button between departments, thus realizing the purpose of non-interference of communication between departments.
Implement dual group standby communication through two PTT bu-ttons;Taking the hotel scene as an example, the side PTT is the overall intercom bu-tton of the hotel, and the front PTT is the intercom bu-tton between departments, achieving the goal of non-interference between departments.