Support number for cell booster.

I am looking to purchase a cell booster - where can I get tech info ? I don’t want to spend 229$ without asking a few questions 

Click on the links on @OttoPylot 's post above.  Ask questions here about what you don't understand. 

@schmidt1x  You can ask here or read thru my Cell Booster Technical Guide, the link is the first one in my sig line. Keep in mind that AT&T's Cell Booster is not an actual cellular booster, it's a femtocell. The naming is confusing but it was a marketing decision.

To start you off, the Cell Booster requires a post paid AT&T cellular account and a land-based internet connection (DSL, cable, or fiber). It uses your internet connection to reach AT&T's Mobility Servers. The system is open. In other words, anybody with AT&T cellular service can access the Cell Booster if within range. That's not that big of a deal if you live in residential home but it may be problematic if you live in an apartment where your neighbors are literally on the other side of the wall.

I have a mountain home will no cell coverage. Tried WiFi extender and meshed network from Frontier .  No help.  Was thinking about a cell boost that plugs into the router and bypass the WiFi AP’s . I do not want to add external antennas etc with the poor cover we have 

@schmidt1x  What kind of service do you have from Frontier (DSL, cable)? The Cell Booster broadcasts an LTE signal only so WiFi is of no use. If you have a robust mesh WiFi system (ideally the satellites are hardwired back to the router) then have you tried WiFi-C (WiFi Calling)? Being as you have a mountain home, then location verification, which is required for the Cell Booster, would probably be a major issue. If GPS location can't be verified, then connection to the AT&T Mobility Servers won't happen. A local tower is not required for the Cell Booster to work but it is needed for other operations. Read my Guide. 

The Cell Booster needs a direct ethernet connection to the router. It also has a small antenna (with about a 6' cord) that needs to be placed on or very near a window for GPS, and must remain attached at all times. Some providers make it difficult for the Cell Booster to connect, especially if the provider offers a VoIP service.

With no cellular signal at all then a cellular booster (the second link in my sig line) will probably be of no use either because they require at least one and preferably two bars of signal strength. They are getting better but you still need to place an antenna on your roof and one inside your home. A professional installation is highly recommended, especially in your situation.

WiFi calling does not work- keeps failing. I added mesh network etc same problem.  The idea of cell boost was to bypass the WiFi AP and have cell signal in the house .  Connect direct to router .  TMO and VZ have them.  Nextdoor neighbor has TMO with one they provide for free and works great in that config 

We use a mesh WiFi system, with two hard wired satellites upstairs, and WiFi-C works perfectly. Our WiFi is also very fast and reliable. However, I use my own modem and router which can make a difference. For transparency, I do not use AT&T for my internet service. I only setup the Cell Booster every couple of months to keep my account active and to get any updates that may be available. Keep in mind, that the femtocells have nothing to do with your in-home WiFi signal. Two entirely different technologies.

What are your internet speeds?

You can try AT&T's Cell Booster just be aware of the return window in case it doesn't meet your needs. Other than the Cell Booster, WiFi-C (WiFi Calling) is all that AT&T offers to improve in-home coverage. You can always switch to TMO or VZ if you think their femtocells might be a better fit for you. 

Speeds, 90 down and 20 ish up .  

The absolute download/upload minimum for the Cell Booster is 5Mbps/1Mbps, but ideally you'd want up to 100Mbps down and 5Mbps up. At 90/20 you should be ok if that is stable and jitter is very low. Is that cable or DSL? Oh, and the Cell Booster does not support wireless internet (satellite or WiFi). It can work but if there are issues, which there will be, AT&T can't help you. That being said, there are some very positive reports with Starlink.

The Cell Booster Pro is the other AT&T  femotcell option but it is expensive with a few more options but the setup and operation are the same.