The Annoyance:

My home alarm started behaving strangely after I had DSL installed. Is there a way to fix this?

The Fix:

Simply put, DSL is broadband Internet access that runs over your existing telephone line. DSL service can coexist on your telephone line because it uses a different range of frequencies than conventional phone and fax equipment. However, other telco devices in your home can sometimes affect (and be affected by) the DSL service. To eliminate the interference, install a filter at each telephone jack in your home. Inexpensive filters prevent most telephones, fax machines, and other gadgets from interfering with your data service. You can buy inexpensive DSL filters from any computer store, including CompUSA, Staples, or OfficeMax.

However, filters are not a universal cure for device interference. If you can’t overcome interference with filters, you may have to install a splitter to completely separate data from voice signals. Homes with alarm systems or TDD systems (devices for the deaf) often require a splitter at the point where telephone wiring enters the home, and separate cabling to a phone jack set aside for data use. Contact your DSL service provider. They may be able to test your home wiring, install the splitter for you (if necessary), and even install the additional wiring and jack for your data access.


Remember that telephone companies typically charge for any in-home wiring work, so be sure to understand any additional charges ...

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