One of the downsides of living rural is the lack of cellular coverage, at least in my neighborhood as I’m lucky to get a signal on my T-Mobile phone and have a weak signal on my Verizon phone in my house. The folks at MyAmplifiers.com think they may have the solution with their AnyTone AT-400C CDMA Cellular Repeater, so I jumped at the chance to give their mobile phone booster a test drive. If nothing else, it turned out to be a learning experience.
My first mistake was that I looked at their website and the AT-400C page shows a picture of a device with the letters GSM printed upon it. Not thinking, I assumed (I know what assumed means ), that it would amplify my T-Mobile cell phone signal. When the package arrived in a plain white unmarked box, I was surprised that the device had CDMA printed on it. I then took a look at the specs.
Indoor coverage: 80 m2
Up-link frequency: 824~849MHz
Down-link frequency: 869~894MHz
Up-link Gain: 30 dB
Down-link Gain: 40 dB
Power supply: DC 9V (AC 220V power adapter supplied)
Working Temperature: -25 to +55 C
Weight: 2 kg
Further investigation revealed that the AT-400C will work for GSM phones, just not in the US. T-Mobile operates in the 1900 MHz band here. Luckily I also have a Verizon CDMA phone that operates in the 800 MHz band, so the review could go on. To be fair, the MyAmplifiers web site does show other models that work for the 1900 MHz band.
A look at the bottom of the cell phone booster illustrates 2 things: the mounting holes are very small and I found it difficult to get a screwdriver past the connectors. And you may have noticed, nowhere on this device is there any indication of who or where this device was made. There was a packing slip inside the package indicating shipping from ShenZen China.
Following the directions for installation that came with the device, I searched around my residence for the best possible signal strength with my Verizon phone. I admit I had some help, because I have a thing about heights. Around my house we found the best signal to be at the roof peak on the second story. Because I didn’t want to punch holes in the side of my house, I went into the attic and found the same signal strength on the other side of the wall, so I mounted the receiving antenna there.
After power was applied to the amp, the strength jumped to 4 bars. This was at a distance of about 2 feet from the antenna. However, the signal strength dropped fast as I moved away from the amp. At about 4 feet I was down to 3 bars and at 10 feet 2 bars was the maximum.
The AT-400C specification states that it is suitable for an 80 m2 space (861 ft2). As my house is 2 story and 2000 ft2 this should cover at least the upper floor. Unfortunately, this wasn’t the case. At any distance greater than 10 ft, there was no benefit to having the amp on. I had the same signal with and without the amp.
Perhaps my results would have been better had I installed the receiving antenna outside on a pole as illustrated in their installation sheet, but I had the same signal level at the same point on both sides of my attic wall. Also, there is drywall between the transmitting antenna and the place where I use the phone which may have attenuated the signal.
I expected more from this device. There are other versions available from MyAmplifiers.com that purport to cover a greater area, but there are some basic issues even if they did work. Compared to vendors of similar devices, the AT-400C is a bargain, but you get what you pay for. To the best of my knowledge they have no presence in the US, for those of us here who would be interested. From what I can glean from the website, their target market is Asia and Europe. I also have a problem when there is no indication on the device about where it’s made or who made it.
This device may work for those who have a strong signal outside which they wish to duplicate in an area of 80 m2 or less. The documentation for the device is confusing. Sometimes the AT-400C is referred to as a repeater and at other times it states that the device will amplify the signal. In my experience it’s probably not for someone who lives in a cellular dead zone, but if you live near a cell tower and want to repeat the signal inside, it may work. Be aware that to install the device correctly, you may need to hire a contractor to mount the outside antenna and run cables to the area you wish to cover.