Siemens Hicom 300 Operator's Manual page 3

Alarm Interrogate - normally disabled. Alarms registered at the
service terminal.
Call charge information - If call charge requested, will give details
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once call is completed.
Night service or Unstaffed mode - All calls arriving after this key
is depressed go to alternate consoles, the night answer stations or
night bells.
Trunk line reservation - This key reserves specific outgoing lines
for the use by the operator, e.g. during peak traffic.
Class of Service Changeover - This LED will be on if one or more
extensions in the system are locked.
Trunk Call Charge - Will be depressed prior to extending call if call
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charges are required for immediate billing needs.
Trunk Group 1 } These two keys can be programmed as dial
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Trunk Group 2 }
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Internal or External Route - To indicate voice channel in use.
Personal Call - Used to answer and set up personal calls. Each
console has its own personal extension number. Can be used when
console is in unstaffed mode.
Operator Key - Used to answer all operator (internal) calls.
Trunk Call Key - Used to answer all Incoming (external) calls.
Paging Facility - Not used on current software.
} keys. Normally used for Tie Lines.
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