Central Filter

Inline Filter

Inline Spliter Filter

ADSL BROADBAND INSTALLATION

Why splitters / filters are needed
When ADSL and PSTN work at the same line at the same time, the electronics inside a normal telephone can be problem for high frequency ADSL signals: the ADSL signals can be attenuated (high capacitance on telephone input, possible resonances inside telephone, impedance mismatch) and ADSL signals can be heard as noise on some telephones (phone electronics demodulates high frequency signal outside it's operating range to voice frequency noise). In order to keep these systems apart and stop them interfering with each other it is necessary to separate the two components from the telephone line in your home.

This is where the Filter / Splitter comes in. The ADSL POTS Splitter / filter allows taking the full advantage of the 1.1MHz copper line frequency spectrum, by stopping the telephone and ADSL systems from interfering with each other.
An ADSL filter is normally a small plastic box with a short lead that plugs into your phone socket and two outputs, one for your ADSL Modem and another for a telephone. Some filters have only one telephone output in them. ADSL filter select the band of frequencies for each of the outputs, phone or ADSL, and send just the correct band to the appropriate socket. The phone output gets only telephone frequencies (from DC to 3.4 kHz) and the ADSL output gets the higher frequencies well (above 25 kHz).

For good system performance it is very important that all your other telephony equipment is separated from the ADSL signals by the use of a splitter / filter -- this equipment includes telephones, answering machines, "normal" computer modems, etc, etc.

Tips:
• All phones or other equipment must pass through a filter.
• Make sure that the ADSL signal is only passing through one Filter / Splitter.
• If you have more than 3 phones and/or answering machines than a Central Filter should be fitted to the premises.