Cel-Fi Duo+ | Verizon | Plug & Play Smart Signal Booster for Home or Small Office

Spent quite a bit of time researching and setting up the system. Technical support was very helpful. The system was operating correctly but did not improve my Verizon cell signal despite many days trying to make it work. So I returned it.

This device works great. It's exceptionally easy to set it up. But, if you have a prepaid Verizon account, you CANNOT register this device with them (VERIZON) and will be in violation of FCC laws. The only way you can use this device is with a postpaid account which is more expensive (in our case $50.00 per month) and offers less data traffic. Nowhere on Verizon's site do they advise you of this. Cel-Fi does not provide this information either. Caveat emptor!

Finally a solution for our cell phone problem, AND for once a product that is truly plug and play! Started with minimal service and 'bars' in our rural western NC location (we have Verizon). Bought a different product with professional installation and an outside antenna, did nothing. Went back to Amazon to find something else to try and found this. It appears you must make sure you buy the specific model for your cell company. We had 2-3 bars and could not make a call unless we stepped outside in the exact corner of our deck, and even then people got every other word, frustrating to say the least. So... it arrived and I was cautiously optimistic. From research online some reviews say you must have a 4G or LTE signal on your phone or it wont work. My iPhone only showed bars so I was not sure the type of signal I had until I turned off Wi-Fi, then that icon went away and next to the bars my phone then had space for the signal type, mine showed 5G. Followed directions and placed Network Unit upstairs as far from downstairs living room as possible, and in a window with some cell coverage. Waited until it 'locked on' to signal. Plugged in Coverage Unit and waited a few moments, a 4 showed on display, optimum is 8 or 9 according to directions. FULL bars on phone, calls crystal clear!! Now after about an hour display is showing a 5, good enough for me, not going to touch is or move it. $650 not cheap but excellent call quality and an un-frustrated family makes it worth it!

The good news is, this product can boost your cellular signal significantly. The bad news is you have to do all the work. After days fiddling with this things, my advice is toss the directions and do the following: 1) Unpack the “Network” unit. Whoever named this needs a different job. It’s an antenna, nothing more. Put the unit where you read the most 4G / LTE bars on your phone. A few things to consider. If you have no 4G / LTE signal, this product is useless, return it. If you have a place in your home with more bars but it says 3G, DO NOT PUT IT THERE. This antenna ONLY receives 4G/LTE. Put it where you have the most bars of 4G / LTE. One 4G / LTE bar is enough. 2) Once you’ve found your location, plug in the “Network” unit. Do not wait for anything to happen. Nothing will happen! The green power light will happily blink forever. The app won’t connect to it. It won’t boost your cell signal. Literally nothing will happen. 3) Take the other unit, the “Coverage” unit, and plug it in somewhere on the other side of your home. This is the transmitter of the boosted cell signal. A few considerations. The two units will communicate via their own WiFi network. It will NOT use your home WiFi network. Cel-Fi creates its own. Keep it away from your WiFi hub or they’ll interfere. The units need a good WiFi connection to communicate, so don’t put it either unit somewhere WiFi can’t penetrate. That means don’t put either unit behind large metal objects, cement walls, and so forth. Ideally both units should be placed up high with a clear line of sight between them. 4) Once the two units are plugged in they should eventually set up their WiFi network and connect. You’ll know this has happened once the green bars on the Network unit appear, and a number appears in the Coverage unit. IGNORE THE NUMBER OF GREEN BARS AND IGNORE THE NUMBER ON THE COVERAGE UNIT. The instructions say an 8 or 9 on the Coverage unit is ideal. It isn’t. An 8 or 9 means you are on the brink of failure! Use the app to place your units. 5) Install the Wave app on your phone. You must stand near the Coverage unit for the app to work. Remember what I said, the Network unit is just an antenna. The Coverage unit is where the action is. Open the app, wait for it to connect via Bluetooth to the Coverage unit. Once it connects go to the Advanced tab. There you will see the cellular bands and how you are doing. Ideally you want everything 100%. If the Signal Strength/Quality circles are low, try moving the Network unit and see if they improve. If the Boost is low, try moving the Coverage unit closer to the Network unit. Note: if you put the two units too close together they will interfere with each other. Too far apart and they will be flaky. I had best luck with a number of 5, 6, or 7 on the Coverage unit, but again, use the app rather than rely on that number. 6) Once everything is set up, you should have better cellular signal near the Coverage unit ONLY! The Network unit doesn’t broadcast signal. ONLY the Coverage unit. You’ll find the thing is somewhat unreliable, however, because the Cel-Fi WiFi network will from time to time conflict with your home and neighbors WiFi networks. The WiFi hubs will eventually sort this out on their own, but while they’re doing that your cellular signal boost may disappear. There you go, you’re all set up. Hope this saves you the hours of frustration I went through getting these things to work.

The system was easy to install however, after 3 hours of trying multiple set ups in my house I quit. I have spaced the two devices as gifts apart as I can and I can still only get a 5(you need an 8/9). I had four bars on the main device which is pretty good at our house because we are lucky if we get two. I could not up the numbers on the receiver unfortunately. Our house Js three bedrooms and a basement. I put the signal device upstairs in the farthest bedroom and the receiver in the basement on the opposite end and the highest I could get was a five. Not sure if this would have worked better if my house was a bit longer. Also, even with the 5 which the app said was ok, my signal did not increase at all?

Sounded like a good option. Worked somewhat off and on but never worked well. Lately after less than a year doesn't work at all anymore. Get a Samsung booster that plugs into your home network and be done with it.

Didn’t work for me. I needed a directional antenna in my location.

Did not help with overall signal strength in my condo..