Requesting An Over-The-Air Rekey (Astro Conventional Only); Global Positioning System (Gps) Enabled; Understanding The Gps Feature - Motorola APX 7500 O5 User Manual

Requesting an Over-the-Air Rekey (ASTRO
Conventional Only)
This feature, also known as OTAR, allows the dispatcher to
reprogram the encryption keys in the radio remotely. The
dispatcher performs the rekey operation upon receiving a rekey
request from the user.
Procedure:
< >
1 or to REKY.
2 Press the Menu Select button directly below REKY.
3 Press the PTT button to send the rekey request.
OR
Press the PTT button again, or the H or Emergency button,
to exit the feature and transmit in normal mode.
4 If the rekey operation fails, a bad-key tone sounds and the
display shows REKEY FAIL.
Note: The rekey operation failure indicates that your radio
does not contain the Unique Shadow Key (USK). This
key must be loaded into the radio with the key-variable
loader (KVL) before the rekey request can be sent.
Refer to your local key management supervisor for
more information.

Global Positioning System (GPS) Enabled

Your GPS Enabled feature uses information from the Global
Positioning System (GPS) satellites orbiting the Earth to
determine the approximate geographical location of your radio,
expressed as latitude and longitude. The availability and
accuracy of this location information (and the amount of time
that it takes to calculate it) varies depending on the environment
in which you are using the GPS feature.
For example, GPS location fixes are very difficult to obtain
indoors, in covered locations, between high buildings, or in
situations where you have not established a clear broad view of
the sky.

Understanding the GPS Feature

The GPS technology uses radio signals from earth orbiting
satellites, to establish the location co-ordinates, maximizing
your view of clear unobstructed sky is essential for optimum
performance.
Where adequate signals from multiple satellites are not
available (usually because you cannot establish a view of a
wide area of the sky), the GPS feature of your radio will not
work. Such situations include but are not limited to:
•
In underground locations
•
Inside of buildings, trains, or other covered vehicles
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