Low Pass Filters; Figure 21. In-Line Filter Installation - D-Link DSL-300G User Manual

Low Pass Filters

Most ADSL clients will be required to install a simple device that prevents the ADSL line from interfering with
regular telephone services. These devices are low pass filters and are variously referred to as in-line filters,
micro-filters, line splitters or split line filters. They are easy to install and use standard telephone connectors and
cable.
For some ADSL clients, a telecommunications technician will be sent to the client's premises to modify the
telephone line, usually at the point where the telephone line enters the building. If a technician has divided or
split your telephone line into two separate lines - one for regular telephone service and the other for ADSL –
then you do not need to use any type of filter device. Follow the instructions given to you by your ADSL service
provider, ISP or telephone company about where and how you should connect the Modem to the ADSL line.
In-Line Filters
Two common styles of low pass filters are shown in this section, the first is an in-line filter and is illustrated in
Figure 16 below. In-line filters are easy-to-install, in-line devices, which attach to the telephone cable between
the telephone and wall jack.
Note: Do not install an in-line filter between the Modem and the telephone jack. In-line
filters are only intended for use with regular telephones, Fax machines and other regular
telephone devices.
DSL-300G ADSL Modem User's Guide

Figure 21. In-line Filter Installation

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