VTech tz 2551
Almost every state has a free, opt-in "do not call" service, which renders moot the primary feature of the VTech TZ2551 cordless phone system. The phone offers a digital-spread-spectrum cordless phone with a built-in, three-mailbox digital answering machine in the base station, but it's hard to overlook its many flaws.
This phone's main selling point is the TeleZapper feature. TeleZapper emits a signal that tells predictive-dialing computers (which just dial numbers sequentially until someone answers) that your number is disconnected. Since our test lines are doubly protected by both the New York "do not call" list and by caller ID blocking, we could not test TeleZapper's effectiveness. Regardless, TeleZapper is more gravy than it is a reason to buy this model.
Although the box reads "2.4GHz," the TZ2551 is actually a hybrid phone. The 2.4GHz is used only for your end of the conversation, from the handset to the base. Your caller's voice travels from the base to the handset using the more interference-prone 900MHz bands, although neither our Wi-Fi setup nor the nearby microwave oven seemed to cause any undo interference.