Tyco Electronics M7200 - Manual (Page 37)

MM-011553-001, Rev. A
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If a secure call is in progress elsewhere and the user has not logged in, the bottom of the dwell display
will alternate between “No Access” and the alias of the radio that is currently engaged in the secure call.
6.30.2 Manual Encryption (System Model)
Two or more users can manually encrypt a call, if enabled, without an established encrypted talk group. A
pre-determined key is required at each radio.
The key must be pre-determined by the users prior to making a manually encrypted call on
a talk group and is entered into the radio using the keypad. For 128 bit encryption, this key
is between 1 and 16 digits. For 256 bit encryption, this key is between 17 and 32 digits.
If two communicating radios have different (manually-defined) keys, receive audio at each
radio will sound garbled.
With manual encryption enabled, unencrypted radio users on the talk group can still make standard voice
(unencrypted) calls on the talk group. However, if an unencrypted user attempts to transmit on the talk
group when one of the encrypted users is already transmitting on the talk group, the unencrypted radio
will sound a deny tone and “No Access” will appear in the display. Also, the encrypted user can hear
standard unencrypted calls, but cannot respond while still manually encrypted.
CAUTION
Do not set a talk group for manual encryption if it has been set for encryption by the
network administration personnel.
Perform the following to transmit or receive manually encrypted calls:
1. Press *32 on the keypad.
2. Enter the key (1 – 16 digits for 128 bit encryption; 17 – 32 digits for 256 bit encryption).
3. Press the # key.
4. To end manual encryption, press *33#.
If a user is engaged in a call on a talk group that has been manually encrypted at the radio level, the user
will see “Secure Call” on the bottom of the dwell display.
If a secure (encrypted) call is in progress, and the user has not entered the key, the bottom of the dwell
display will alternate between “No Access” and the alias of the radio that is currently engaged in the
secure call.
Once the user has terminated manual encryption, “UnSecure” appears temporarily in the bottom line of
the dwell display.
6.31 PRESET BUTTONS
The front panel contains three buttons labeled A, B, and C.
By holding one of these buttons down for approximately three (3) seconds, the following current
information is saved to the function of that button:
•
Selected talk group
• Selected profile
• Selected priority talk group