updated 08:50 am EST, Tue December 2, 2008
First Look: Cell Ranger
Every cellular phone network has weak spots in certain parts of town. If you're constantly dropping calls in these areas, you could simply avoid making calls there, or you could plug the Cell Ranger into your car's cigarette lighter. The idea behind Cell Ranger is to boost any cellular network's signals so you can connect and make phone calls in formerly poor-coverage areas. (Curiously, the manufacturer notes that this unit does not work with Sprint/Nextel cellular networks.)
The device consists of an antenna on a magnetic base, a long cord, and a plug that fits into the cigarette lighter. Installing it just requires attaching the antenna anywhere on a car (the trunk, the roof, etc.), threading the cord as necessary, and plugging it into the lighter.
Since the antenna base is magnetic, you can easily unplug the Cell Ranger, carry it with you and plug it into another car, such as a rental. You can also leave it plugged into a single vehicle, but the manufacturer warns that leaving the antenna base attached can result in discoloration of paint over time.
Whether you want to use the Cell Ranger as a portable device or not, you'll need to thread the cord through your car, which is probably the hardest part of setting it up. The manufacturer recommends that you snake the cord through the trunk and under the carpet inside your car. For portable use, it's possible to just jam the cord through a window or door, since the cord can work perfectly well despite being crushed.
To test signal strength with an iPhone, you need to put your iPhone into Field Test mode, which you can do by typing *3001#12345#* into the keypad and pressing the Call button. In the upper-left corner of the screen, you'll see the signal strength represented by a number. The higher the negative value of this number (such as -101dBm), the weaker the signal. A strong signal should be near the -70dBm range.
The manufacturer claims that the unit can boost signal strength by 10-15dBm, but in several tests in different areas, the signal strength actually increased by nearly 15-20dBm.
Of course, the unit can't create signals in completely dead spots where no reception exists, but it does do a remarkable job of strengthening signals to reduce the chance of dropped calls or spotty reception.
With many places banning the use of cellphones while driving, the peripheral may only be useful if you regularly make calls while parked. Still, the Cell Ranger works as advertised and if you're willing to pay its $149.99 price, you'll find it invaluable for improving your connection when making calls or using a cellular modem.