Does a Fax Mess with DSL?

Fax machines can affect a DSL signal.

Fax machines interfere with DSL lines, because they run over the same medium, copper telephone lines, according to Tech FAQ. You can prevent fax machines from interfering by using a DSL splitter.

Function

Fax signals affect DSL signals because faxes use the analog--low frequency--spectrum, while DSL uses the high frequencies on a telephone line.

Solution

A DSL splitter is a relatively cheap option that eliminates all interference from low-frequency devices, such as a fax machine. Most DSL providers install splitters for you if you have any analog devices.

Tip

Some Internet service providers send their customers DSL filters instead of installing splitters. Splitters are installed directly on the phone line, while filters are plugged into the phone jack. You may want to request a splitter instead of a filter, because filters are less effective than splitters, according to the Home Phone Wiring website.

References

• Tech FAQ: DSL Splitter
• Home Phone Wiring: An Overview of Wiring Requirements to Support Residential DSL Service