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Volume and tone adjustment: By definition, an amplified phone must raise the volume of the speaker on the other end of the line.We included in our research only those phones that have been certified compliant to the standard, which is fairly common but not ubiquitous. “When somebody has a hearing aid, or a cochlear implant, or a bone anchor device,” she said, “there could be some noise on the line.” TIA-1083 (PDF) is a standard authored by the Telecommunications Industry Association that addresses cordless phone interference when a hearing aid is used in the telecoil (T-coil) mode. Hearing aid compatibility: The HLAA’s Lise Hamlin told us that the first thing someone shopping for an amplified phone should look for is hearing aid compatibility.
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With a full-duplex speakerphone, both parties can talk without having to worry about their conversation being clipped. “A device that is half-duplex can send or receive data, but not at the same time, such as a walkie-talkie,” explains VoIP comparison site GetVoIP. Full-duplex speakerphone: Full-duplex support (as opposed to half-duplex) is necessary if a speakerphone is present.As Ruth Wilson, marketing chair of the DECT Forum, explained to us, this short-range communication technology is ideal for cordless phones because it operates on a wavelength far away from those of Bluetooth, Wi-Fi, and other signals on the wireless spectrum that could potentially interfere. DECT 6.0: This is the wireless standard that allows a cordless handset to communicate with the base, and it’s included in nearly any phone you can buy today.Though we think all cordless phones have annoying menus, some are less frustrating than others. You have to use fixed keys that aren’t necessarily in an intuitive place, and you must use T9-style typing (imagine texting on a cell phone with a fixed number pad) when you fill your address book with names. Intuitive menu systems: On cordless phones, menus and navigation are universally bad compared with the touchscreen smartphone interfaces people are now accustomed to.
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In our research, we gave bonus points for any feature that stopped the phone from ringing unless it was someone we wanted to hear from. More-advanced phones offer pre-screening that prevents robocalls from getting to you in the first place.
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On some phones, this is an active thing-you press a button when a spam call comes in, and that number moves to a block list so it’s blocked going forward.
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