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Is someone in your household monopolizing the phone? A two-line phone might be the solution.
Image by Bob Elsdale/Getty ImagesIf you grew up with a family member who always dominated the phone, you already know the appeal of having multiple lines. No longer will you worry about the person who never lets go of the phone. A two-line phone also lets individuals working from home keep their personal and business calls separate.
Business travelers rely on them. Two-line phones are now a common feature in most hotels, along with services like Internet access, MP3 player connections, and ergonomic chairs. These phones also allow dial-up Internet users to browse the Web while staying connected. Two-line phones merge two distinct phone lines (with separate numbers) into one device.
If you have one of these phones, you may have wondered how two separate phone lines can operate from a single device. After all, single-line and two-line phones look strikingly similar and connect in the same manner. So, what's the secret?
Unplug the phone cord and inspect it carefully. You'll likely notice four wires inside. Some cords have more or fewer, but the standard is four. If that's the case with yours, then surprise—you’re set up for two lines. It turns out that one phone line only uses two of those wires, leaving you with two extra. To activate the second line, simply contact the phone company and ask them to enable the remaining wires for the second line.
In this article, you’ll discover how callers can use two phone lines on the same phone. The next time another call comes through while your family member is deep in conversation, you'll understand the mechanics behind it. Then, learn how two-line phones function so you never miss a call.
How to Connect a Two-Line Phone
Two-line phone splitters offer an alternative to two-line phones. They work by redirecting one line to a single-line phone, and the other line to a separate single-line phone.
The options for two-line phones are seemingly endless. Retailers showcase a wide variety of phones with multiline capabilities. From two-line business phones to two-line touch phones, and even two-line cordless phones. There's even the option of two-line cell phones now.
All telephones feature a jack where the phone cord is plugged in. This jack is connected to the wall jack, which in turn links to the telephone company's wiring. The phone jack contains contacts, or conductors, that detect the wires inside the cord and establish a connection with the line. While the contacts in a two-line phone jack can automatically recognize all four wires and thus both lines, the contacts in a single-line phone jack only detect the first line. So even if you have two active phone lines, plugging a two-line cord into a single-line jack will only allow calls from the first line.
Two-line phones immediately detect both phone lines and identify which one is receiving a call. While it's possible to use two lines without a two-line phone, you would need to either rewire your wall jacks or purchase a two-line splitter. These devices plug into a standard two-line jack and divide the line, sending the first line to one jack and the second line to another. With a splitter, you'll essentially have two single-line phones connected to the same jack—one phone will handle calls from line one, and the other will handle calls from line two.
In the end, two-line phones aren't much different from their single-line versions. Explore the inner workings of these versatile devices on the following page.
Several cell phone carriers now provide second-line service on individual devices. This feature allows you to add a second phone line with a different number to your existing phone. All that’s needed is a second service plan. With two lines on the same phone, you can assign different ringtones, subscribe to different services, and even have phone numbers with different area codes. Two-line cell phones are ideal for people who want to keep their work and personal calls separate.
How Two-Line Phones Work
Two-line phones typically have separate jacks for line one and line two, along with a combination jack that can recognize both lines.
Image by Stockbyte/Getty ImagesIf you've done your research, you likely understand how single-line phones operate from the Mytour article How Telephones Work. While single-line phones have only one jack, two-line phones usually feature two or three jacks. If your phone lines are not combined into one cord, you would plug the first line into the first jack and the second line into the second jack. If the lines are merged, you simply connect the single cord into the third jack, which is designed to detect all four wires.
At their core, two-line phones function the same way as single-line phones—they just have twice the components. The conductors in the phone jack identify whether one or two landlines are in place and then allocate each line to the correct user interface. Line one is managed by one interface, while line two is controlled by another. Condition detectors inside the phone check if the lines are connected to landlines and operate based on this information. These detectors determine which phone line to use based on preset conditions, like the phone number associated with each line. Two-line phones also utilize opto-isolator mechanisms to keep the line circuits isolated and prevent interference or cross talk between the lines.
Two-line phones provide flexibility depending on how the phone lines are configured. Occasionally, only line one will be active, sometimes only line two, and other times both lines are engaged. An internal switching mechanism identifies when a line is in use and triggers a light on the phone to indicate which line is being used. Depending on the specific phone model, there may be additional mechanisms for features such as hold, intercom, and conference calling. Conference calls allow the user and both parties on line one and line two to communicate together.
Although six- or twelve-line phones are commonly used in larger businesses, two-line phones still serve an important purpose. No matter which two-line phone you choose, if you have a lively household, the added line functionality will make you question how you ever managed with just one. For more information on telephones and two-line models, check out the links on the next page.
