Cell phone signal booster

[W1RKW]

Anyone have any experience with cell phone signal boosters?

Cell phone reception is poor here and was thinking of getting one to make XYL happy so she doesn't have to run to the 2nd floor to use her phone..

Was wondering if anyone who uses one has had any issues with amateur band RFI/EMI?

[W4EWH]

Anyone have any experience with cell phone signal boosters?

Cell phone reception is poor here and was thinking of getting one to make XYL happy so she doesn't have to run to the 2nd floor to use her phone..

Was wondering if anyone who uses one has had any issues with amateur band RFI/EMI?

There are 2½ kinds of "signal booster" that I know of, so the first thing I'll do is separate the different types:

• I use a carrir-specific "femtocell," which is an cellular-to-VoIP converter that depends on being connected to the Internet. It cost about $275, and it gives good signals throughout my house, but only serves Verizon and those virtual carriers that lease Verizon facilities.
• There are also bi-directional RF amplifiers, which cost around $850. Although they will handle more than one carrier, the price was prohibitive for me.
• If you have a good WiFi signal throughout the house, most recent cell phones offer service via WiFi. This is the lowest-cost option, and works for any carrier with a compatible phone.

If you have, and plan to keep, a "high speed" Internet connection, see if WiFi connectivity is available on your phone. If not, the femtocell may be the best choice. It depends on the Internet connection being up, so it's not reliable during power outages, but the investment is a lot more modest and the setup is much simpler.

If there are different carriers in use in your household, such as AT&T and Verizon, then you'll be limited to either WiFi connections or an RF amplifier. In the later case, you'll need to check the line of sight to the cell tower, and plan for a mount and/or tower if needed.

HTH.

Bill, W4EWH

[Opcom]

I read that if implementing your own cell repeater, you have to use accepted devices and register your site (home farm whatever) with the carrier, which usually is free, just a form.

[steve_qix]

I have a cell phone bi-directional amplifier (repeater) in my car.  It makes a *huge* difference when signals are weak.

It is a Wilson (forget the model number) and cost around $500 at the time.

[WA2SQQ]

I would think that enabling Wi-Fi calling on your phone would be the easiest and cheapest option. My carrier, T-Mobile, offers it on all their phones. I think the original concept was to save "minutes" before most carriers adopted unlimited calling. I especially like it when I travel abroad - as long as you use WiFi calling, its 100% free.

[W1RKW]

my only concern with a booster is the incoming signal.  I have no idea what the signal strength would be on the boosters receive end. The antenna would go in the attic which is another 10 or so feet above where she can get a weak signal. If the signal is weak like the cell phone on the 2nd floor a few feet below the attic there may not be any benefit. Don't want to spend $$ to find out it won't improve things.  I'm not a gambling man.  The wi-fi calling option seems like it could do the trick though.  Wasn't aware of that option.

[W3SLK]

We have installed a few at work because of the river valley and metal buildings. Usually consist of a small yagi array for outside and a monopole inside. I have DSL that's about 1-S unit this side of reliable and I wanted to get one for my home but the cell signal is very weak non-existing that I would almost need a 70' tower just to get some semblance of a signal!

[John K5PRO]

I have used them for about a decade at this QTH due to marginal signals inside. We have adobe walls and there is chicken wire there embedded under the stucco coating. Its not 100% Faraday cage but it made different rooms loose cell and hangup. My first one was only for the old 880 and 1900 3G Cell bands. After 4G/LTE came, it wasn't working much of the time. When I replaced it, the antenna was rotten and fell apart, a cheap omni. Last fall I searched far and wide and settled on a Nextivity Cell-Fi Go booster, which is impressive. I found one used on EBAY so it wasn't as pricey as new. These are essentially BDAs with adaptive gain control that keeps them from oscillating. They have a blue tooth port and an app on the phone that can check the signal levels, the gain in dB, and so forth. Great for us nerdy engineers and techs. They make several flavors, but for optimal performance I chose the single service specific unit so it looks for LTE around 750-760 Mhz. If I want, I switch in the app, to AT&T or  T Mobile, and it will then optimize that. First I used a Wilson 3122203 Colinear antenna having some horizontal gain all around, but the booster didn't work well or at all. I put the spectrum analyzer on the feeder and saw lower than -90 dBm for 732, 750, 865, 888, 1938, 1968, 2128 and 2150 MHz, all points that are in the midst of various bands. Eventually I ordered a Cel-Fi Yagi and set it up aimed at my main provider, Verizon. Photo attached. This raised all my signals to -78 to -80 dBm and now it works perfectly throughout the house. The only one that is out is 732 which is off the back side of the Yagi, can't have it all. So people visiting us might find that one of the providers isn't strong here. I have a dome antenna on the ceiling in the living room, next to the booster, mounted up near the ceiling. Every once in a while I go on the app, change the service and let it upload firmware revisions, which it always seems to have. It does this via Bluetooth so I am not using cellular data for that. Some of the spectrum measurements are attached. I am very happy with the booster I got, once I put up a good antenna outside. My neighbors want one now, I see them standing in their yard making phone calls. Not to mention browsing the net..

[W4EWH]

I'm the moderator of The Telecom Digest (http://www.telecom-digest.org), and I got the following in a post from one of my readers today. This is from a Verizon notice:

We are moving all devices to our HD Voice LTE network, which offers
superior coverage and performance compared to previous generation
networks.  Starting January 1, 2020, Verizon will no longer allow any
CDMA (3G and 4G Non-HD Voice) 'Like-for-Like' device changes.

Caution Currently, 3G / 4G non-HD Voice CDMA devices can't be
activated for any new line of service.

https://www.verizonwireless.com/support/knowledge-base-218813/

... which means that cell boosters that are limited to the 3G or 4G world will soon be obsolete. I don't know the reason, other than selling a lot of new phones, but it has to figure into any buying choice for cellular booster equipment.

Another reader responded that ...

It had previously been announced (and posted in this newsgroup) that
Verizon's IS-2000 network would be turned down at the end of 2019.
Later it was announced that they were postponing the shutdown until
the end of 2020.  Presumably they found out that a lot more of their
commercial customers had IS-2000 devices that were not about to be
upgraded.

I have an old EndRun Technologies CDMA timecode receiver that I'll be
sad to shut off when Verizon finally does get around to turning down
CDMA service.  We don't have roof access so it's the only way to get
submillisecond-accurate UTC in our machine rooms.

-GAWollman

--
Garrett A. Wollman    | "Act to avoid constraining the future; if you can,
wollman@bimajority.org| act to remove constraint from the future.  This is
Opinions not shared by| a thing you can do, are able to do, to do together."
my employers.         | - Graydon Saunders, _A Succession of Bad Days_ (2015)

Long story short, Verizon is retiring a lot of tech, and a lot of customer equipment is going to be stranded.

Bill, W4EWH