How to install DSL and a burglar alarm on the same telephone line

Written by patrick nelson
  • Share
  • Tweet
  • Share
  • Email

Burglar alarm systems use telephone lines to communicate with central monitoring stations, often the same lines used for DSL Internet connections. DSL can interfere with the alarm system, and the alarm system also can interfere with the DSL service, so a filter is required. Alarm systems need an in-line alarm system filter that makes sure the DSL does not interfere with the alarm system.

Skill level:
Moderately Easy

Things you need

  • Alarm system DSL filter

Show MoreHide


  1. 1

    Remove the alarm panel's phone plug from the home's RJ31X jack (the typical phone-line jack).

  2. 2

    Insert the alarm panel's phone cord plug into the RJ31X jack on the filter.

  3. 3

    Plug the alarm filter into the home's RJ31X jack.

  4. 4

    Test the DSL and the alarm. The filter performs three functions: it filters the DSL signal, it passes the DSL signal on to the home's phone wiring, and it filters the alarm panel's connection to the home's phone wiring. Make sure that you can view a streamed video without interruption while you are testing the alarm. Press "test" on the alarm and enter your code. Follow the prompts to run the alarm test. Have another person monitor the video. Ideally, the DSL should not be interrupted during an alarm communication with the outside telephone network.

  5. 5

    Verify the alarm panel is able to take control of the phone line while still allowing DSL signals to pass through. Make sure that while you are streaming a video the alarm can access the phone line and call your cell phone or the central control station. Check with your alarm-service provider to be sure that the test call worked.

Tips and warnings

  • Sometimes a DSL signal will be reset by the alarm during an event. This is normal---but it should reconnect. If it doesn't reconnect, reboot the DSL modem.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.