Mdm (Modem Module) - Comdial DX-80 Installation And Maintenance Manual

Each CO line circuit incorporates over-voltage protection, ring detector, loop detector, loop/pulse-dial relay,
current sink circuit, coupling/isolation transformer (impedance 600:600), hybrid circuit, CODEC & filter,
polarity guard circuit and Radio Frequency noise filter.
The fourth CO Line port is equipped with CNG Fax Tone Detection circuitry. When programmed as a "FAX"
line, this circuit will automatically engage the FAX Tone detector. If FAX tone is detected, the call is routed to
the analog port designated as the destination for fax calls.
Power Failure
Transfer port
– associated
to CO Line
port 1
CO Line ports
1~4. (Circuit 4
equipped with
CNG FAX
Detect)

MDM (Modem Module)

The Modem Module is a self-contained integrated modem unit that is installed at JP5 and JP6 in the upper
right corner of the CPM. The integrated Modem Module allows the servicing Telephone Company to access
the telephone system programming and remote maintenance utilities from an off-site location (password
verification required). When the MDM is used, the remote location programming is done via the proprietary
DOS-based PC program "PC-DBA." This program can be obtained free of charge at the Comdial Web site
www.comdial.com or from the Comdial Customer Services Department. (Diskette and shipping charges may
apply.)
When installed, the servicing technician uses PC-DBA and a modem (in the PC) to place a call to the site
where the DX-80 is installed. If one of the voice processing systems are installed, routing to the modem
extension is automated. Otherwise the person who answered this data call must transfer the call to
Extension 199*. Once the modems have established the data connection, PC-DBA may be used to perform
all servicing operations.
(*The MDM default extension number is 199. This number can be changed and therefore may be different
for some DX-80 systems.)
P7290 IMM
DX-80 I M
NSTALLATION AND
Figure 5: COM4 (Central Office Module - 4 Port)
1-10
M
AINTENANCE ANUAL