External telephone ringers bridge the connection between your telephone jack and your telephone and are activated when a signal passes through the cord, indicating a telephone call via much louder-than-normal ring. Some ringers have multiple volume settings, from relatively loud to mind-melting loud. External telephone ringers are compatible with normal land-line phones and cordless phones.
Connect the telephone line from your wall outlet to the "Line" or "In" jack on the external ringer.
Connect a separate telephone line from the "Phone" or "Out" jack on the external ringer to the "In" jack on your telephone base.
Install the batteries in your external ringer if required. Some external ringers use a standard AC power adapter; if yours does, connect the adapter to the external ringer and connect the plug to your wall power outlet.
Mount the external ringer if desired. The ringer will work whether mounted or not, but mounting it could prevent it from being damaged by someone stepping on it or tripping over it. Your ringer will come with a mounting plate and the necessary hardware.
If you're installing the ringer far from your wall phone jack, you'll need a longer telephone cord. Secure the cord against the base of your wall to avoid creating a hazard.
Adjust the tone and volume. Most external ringers have several tone options and adjustable volume. If your ringer has a "Test" button, press it to help you determine the desired volume level.
Things You'll Need
Telephone cord (usually included with ringer)
Some external ringers are mechanical; they use a standard bell to amplify your telephone's sound. Install these ringers in the same manner unless instructed otherwise; no battery or AC adapter is required for a mechanical ringer.
Don't use an indoor ringer outdoors; it isn't designed to handle the elements.