SDP660 – USER MANUAL
TNM-U-E-0114
Jun 15 (Iss. 1.4)
Page 53
SPECIAL FUNCTIONS
8.10
R
ESET
The Reset function is usually assigned to the F6 key, and is used as a cancel function when in a
menu or as a backspace when entering keypad dial-strings.
8.11
S
PEAKER
M
UTE
The speaker mute function key will mute the audio output to the speaker. Pressing the function
button again will again allow audio to be heard at the speaker.
8.12
M
AN
D
OWN
The Man Down function provides support for the radio’s automatic alarm sequence to be executed
if the radio’s inbuilt accelerometer senses certain unusual patterns in the orientation and
movement of the radio.
The detection process uses an orientation “learning” period, immediately after the man down
function is enabled, to establish how the radio is normally held.
Once this is established, any significant and prolonged deviation from this orientation or an
unexpected acceleration is considered to be an alarm event.
The radio also senses normal walking movement. If this stops for a period of time, this is also
considered an alarm event.
Once the Man Down function is triggered, a warning beep will sound and the operator has a set
time to disarm the sending of an Alarm Status using a programmed “Man Down” button (see
buttons).
The Man Down system sequence is:
The r
adio’s man down system is enabled by pressing the allocated Man Down button.
The r
adio uses a 3D accelerometer to determine the direction of the gravity’s 1 g downward
acceleration. The direction of this force is averaged during the “learning” time.
Once trained, the gravity component of the acceleration is removed, leaving only movement,
impacts and mis-orientation acceleration to be sensed.
User movement is monitored for the normal patterns of acceleration associated with the
walking movement.
Mis-orientation is indicated by the gravity force
not being cancelled by the “trained” counter-
force.
Falls, impacts and other unexpected trauma can be sensed by sudden accelerations that
exceed the force of gravity.
If any of these events occur, the Man Down audible alert is triggered.
The user has the set time to cancel the alert or the radio will enter the emergency alarm
mode (see Alarm).
Then the Man Down system uses the radio’s emergency automatic voice transmission
sequencer, programmed by the Alarm settings, to monitor the audio at the scene of the
incident.
8.13
L
ONE
W
ORKER
Lone Worker is used to initiate emergency alarm mode when the user is unresponsive after a
predetermined time. A data message is also sent to the device management software (via the
gateway) indicating that the worker may be incapacitated.