Motorola STU 111/SECTEL 1000 User Manual page 54

@
End call by hanging up, or pressing
I
RESET
I .
and dialing
another number (this may be done from either the secure or
clear mode). If the other party terminates the call, the
message display will show:
VOICE
2.4
Half Duplex Calls
The half duplex mode of operation is useful when there is too
much interference on the phone line to use it for secure voice/data
communication. Follow the procedure below to operate in half
duplex:
G)
Ensure your CIK is inserted and turned one-quarter turn
clockwise.
NOTE
The CIK must remain inserted while the terminal is in secure mode.
NOTE
Once the CIK is inserted in the STU 111/SECTEL 1000. the terminal and CIK
become classified to the level you are keyed. Consult your security procedures
for instructions on how to properly handle the equipment.
@
Place a clear call and establish contact with the person to
whom you will be communicating in the secure mode. See
the paragraph above, PLACING CLEAR MODE CALLS.
@Tell the person you want to establish a secure conversation.
@
Verify that the VOICE annunciator on the message display is
on. If it is not, press
I
VOICE/DATA
I .
@
Press
I
HALF DUPLEX
I .
The HD annunciator on the bottom right
corner of the message display will appear.
NOTE
If one of two terminals is in the half duplex and secure mode, the other terminal
will be converted to half duplex automatically by going secure.
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