Total Control MP/16, Руководство оператора

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4-22 Leased Line
Leased Line
The following operations apply in installations where the modem's
phone line is not part of a public-access switched telephone
network. Instead, the modem is connected to a special user-
installed telephone line or a line that is leased from the telephone
company. These lines are often referred to as
dedicated (to a pair of
modems) or
private
lines.
In both types of installation there is a continuous point-to-point
connection between two modems. No dialing of phone numbers is
required. The modems may be in either Smart or Dumb mode
(determined by the position of DIP switch 8).
The User-Installed or
Leased Telephone Line
User-installed lines are most commonly 2-wire lines, similar to the
2-wire lines that connect residential phones to the public switched
network.
If you are leasing a line from the telephone company, request a 2-
wire line, the type of line the modem is designed to work with. If
the telephone company only makes a 4-wire line available, you'll
need a 4-wire to 2-wire converter at each end of the connection. If
the phone company does not install the con verters, you will have
to supply them.
For optimal operations, we recommend that the physical length of
these lines not exceed 5 miles.