ZETRON 748, Техническое руководство

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025-9368H v
INSTALLATION AND OPERATIONAL WARNINGS (Continued)
WARNING:
Although this equipment can use either loop disconnect or DTMF signaling, only the
performance of the DTMF signaling is subject to regulatory requirements for correct
operation. It is therefore strongly recommended that the equipment is set to use DTMF
signaling for access to public or private emergency services. DTMF signaling also provides
faster call set up.
This apparatus has been approved for the use of the following facilities:
MODEM
Auto-Answering
Auto-Clearing
Auto-Calling
DTMF Signaling
Any other usage will invalidate the approval of the apparatus if as a result it then ceases to
conform to the standards against which approval was granted.
WARNING:
When programming Auto-Dial numbers, the user must check and insure that all numbers are
correctly programmed.
The Model 748 has a Ringer Equivalence Number (REN) of 3.0.
A single telephone line has a physical limit to the number of ringers that can be connected
and still provide reliable operation, Each type of apparatus will be marked with a REN value
(a typical BT provided telephone instrument has a REN of 1.0 - unless otherwise marked).
The maximum REN value for a single line is 4.0.
The maximum number of ringers that may be connected to a specific telephone line is
determined by adding up the individual REN values of the desired instruments, and insuring
that their total does not exceed 4.0.
The Model 748 is not intended to receive calls from naive callers. A naive caller is one with
no special knowledge of the characteristics of the auto-answering system (Model 748).
If the Model 748 is connected to the Public Switch Telephone Network, the telephone
number must not be made public.
The Model 748 is not suitable for connection as an extension to a pay phone, or for use with
a 1 + 1 carrier system.