Karel DS200, Technical Reference And Installation Manual

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The EX200 (0/8LB) module allows two methods for gain control. First of them is to determine
a permanent gain level for a specific line at the beginning and to set it on the module. The
second method, on the other hand, is to set the gain level temporarily by using hook flash
and keypad during each conversation. This operation can be carried out by the extension
with hook flash authorization on the exchange side only, for a local battery telephone does
not possess hook flash function.
The EX200 (0/8LB) Module, like E&M module, can also be used for inter-exchange
connections.
There is a transformer on the EX200B (0/8LB) card in order to isolate the speech circuit, and
a varistor against the case that a ring is received while the line is active. The ringer signal
coming over from the power supply is directly transferred to the extension through relay
protection.
Connections to the EX200B (0/8LB) card are made over the CON3 line connection card.
VII.3.K. EX200 (4 VoIP) VOICE OVER IP MODULE
In addition to the common circuits explained above, there are 4 VoIP channels on the
EX200B (4VoIP) card. Those VoIP channels work in compliance with the H.323 or SIP
protocol.
When the module is utilized as an external line, institutions/corporations possessing several
DS200 series exchanges can establish the infrastructure that enables phone calls over IP
lines by connecting their exchanges to each other over lines of IP network.
In this type application, “Frame Relay” or “Leased Line” type of lines are usually employed for
data transfer among remote offices. Making phone calls over these very lines as well would
provide advantage towards cutting communication expenses of a corporation.
The EX200 (4VoIP) card works as a gateway that establishes connection between the
exchange and the IP network. Thanks to the EX200 (4VoIP) card, direct voice
communication can be established without the need for interfaces like FXO, FXS for routers,
which are present in the IP networks.
Since the VoIP applications are software-based ones, basic functions are fulfilled by the DSP
on the card.
By way of its intelligent and capable software the VoIP card supports, G711 and G729
codecs, echo canceller, jitter buffer and etc.
Connection to the EX200B (4VoIP) card is made over the RJ45 Ethernet connection on the
front face of the card.
VII.3.L. EX200 (8 VoIP) VOICE OVER IP MODULE
In addition to the common circuits explained above, there are 8 VoIP channels on the
EX200B (8VoIP) card. Those VoIP channels work in compliance with the H.323 or SIP
protocol.
When the module is utilized as an external line, institutions/corporations possessing several
DS200 series exchanges can establish the infrastructure that enables phone calls over IP
lines by connecting their exchanges to each other over lines of IP network.