Hytera PD70X Series, System Planner Manual

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Hytera DMR System Planner
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Alarm mode is used to inform the other radios in the system that you need help.
Those radios will check the ID of the transmitting radio and take actions. This
emergency mode can inform the other users that you are in danger, but it cannot tell
your actual situation. Hence, the other users cannot take correct measures for help.
In this case, you can use Call Only to transmit an emergency call so that the other
users in the system will know your actual needs. The Alarm with Call mode indicates
you can send the emergency alarm and the emergency call together. It is useful
when the current channel is occupied, which blocks the emergency alarm. The
system has a revert channel for the radio to transmit the emergency alarm. You can
define the revert channel on actual requirements. And note that the preset channel
shall be convenient to other users for receiving and seldom occupied. In the revert
channel, the transmitting contact must be a group call contact rather than a private
call contact. To avoid mistaken configuration, the channel on which the transmitting
contact is a private call contact is unavailable when you are setting the revert
channel for emergency alarm.
2.5.1 Alarm
In this mode, after the emergency alarm is enabled, the radio will transmit the
emergency code; when other users in the system receive the code, they will give an
ACK (acknowledge), and then the emergency code transmitting radio will enter the
emergency status. You can set the code to be sent for multiple times, to arouse the
attention of the other users or to avoid transmission failure due to abnormal channel.
You can define the times of emergency code transmission by setting the “Impolite
Retries” and “Polite Retries” in the CPS. An impolite transmission occurs despit of
the occupied channel, while a polite transmission will not take place forcibly. The
polite transmission indicates that radio will wait and suspend transmitting if the
channel is busy, but will transmit forcibly after a certain period if the channel is
always busy. The transmission times will only be configurable during the emergency
alarm or emergency call transmission.
During the emergency alarm, the radio will transmit the emergency code on the
emergency transmitting channel, and will wait for one ACK from the receiving radios.
The radio will retry the transmission and wait for the ACK. When waiting for the ACK,
the radio will only take the ACK code as effective. If no ACK is received within the
transmission retries, the radio will give an indication and quit the emergency status.
When the radio is waiting for the ACK, if
PTT is held down, the ACK is received or
the retries (including all the impolite and polite retries) are all used, the radio will quit
the emergency status.