Cellular Phone Signal Amplifiers

[Corley5]

In our quest for high speed internet we're trying out our cell provider's wireless internet.  The 1st night I tried it it rocked  8).  Last night I went back to dialup  :(  We're on the edge of coverage here and reception isn't always great.  There are 0 bars in places on the farm but we've can usually scrounge at least two here at the house.  If the phones are laying on the desk three bars is common.  I was going to set us up with satellite for Christmas but the Alltel guy talked us into this when we got new phones.  It's not part of the contract and we can drop it anytime if it doesn't work for us  8)  So I've been looking at signal amplifiers and wonder if anyone has any experience with them  ??? 

[Texas Ranger]

I have a signal amp, bought from radio shack, that I have used for the last two years.  It supposedly amps from the .5 watt to 3 watt.  It may well do so, no way to tell, other than:  There is a section of Texas just north of us that is Cingular controlled, no Verizon withing 40-50 miles.  Before the amp, could never have very good reception or transmition, with the amp, just like the rest of the area.  We drove from east Texas to Nashville last year, no interuptions in the entire trip.

The unit is little more than the transmitter from a bag phone, with an external antennae, and a cradle that the cell phone fits into.  A little cumbersome, but worth the security of knowing you will seldom be out of range of something.  Cost around $200.

[scsmith42]

Corley, what you need is called a bi-directional amplifier (or BDA for short).  Typically, you would install some type of mast at your place where you could get line of site to the nearest cell tower.  On that mast you would install a directional antenna, typically of a design called a "yagi".  Run coax down the tower to the amplifier, and have a second, omni-directional antenna for rebroadcasting the signal around your home.

The "bi" of bi-directional means that it amplifies signals both ways.  Usually the problem is not the tower's ability to send a signal throug to you - it's your 1/2 watt phone's ability to get a signal back to the tower. The BDA amplifies both.

Getting your directional send/receive antenna 30 - 50' up into the air is also important, as you want to get above the ground clutter between your place and the cell tower.

Usually, the reason that your signal goes in and out is because of RF interference between you and the tower.  The "bars" on your phone don't represent signal strength, they represent SQE, which is Signal Quality Estimator.  This is a calculation based upon the signal strength and the amount of interference.  In rural areas, becasue there is less interference, the signals usually carry much farther.

When it comes to BDA's, bigger is not necessarily better.  The key is to get as much power as you need, and no more.  In calculating the amount of amplification you typically determine the amount of gain in the antennas, the amount of loss in the coax and connectors, and make sure that you end up a few DB to the positive.

Your cellular provider's RF Engineering team will usually do the calculations for you and tell you what you need.  Be sure to check what frequencies that their wireless data is operating on - it's not always the same as the voice signal.

Let me know if you need further help.  Scott

[Blake22]

You need a steel whip CB antena like mounts on a tool box.

[Dave Shepard]

I use a cheaper alternative to what Scott is talking about. I have a Wilson Cellular (not the CB Wilson) antenna. It provides a 10-15 decibel gain. A system like Scotts will give you more like 60 db. My antenna and adapter was less than $50. The repeater systems are $500-$1000.
I had no bars at my house and the Wilson gave me two. I can also make a clear call that won't get dropped when there is only one bar flashing on and off. Hope this helps. I have Cingular BTW.


Dave

[Corley5]

Thanks for the info guys  8) 8)  I've got to get over to the Alltel store and have a talk with them now.  I was looking at the repeater systems from Wilson but it sure would be nice if an antenna would work  8)

[BigTrev]

Back before I started with Petersons I was working in a electronics store kinda like your Radio Shack. In there I used to sell cellphones to rural customers a lot. So I know for sure those boosters are incredible.

Usually they scale up like a PRS radio as in, 2x the wattage gives you a +50% signal. If your on the fringe like you say then even a little booster will be fine, though a more expensive higher powered one will get you through the bad weather a lot better.

They really are a must with wireless internet as interruptions can cause packet loss which not only leads to poor performance but also decreased security.

3 watts is the norm, 5 watts is the kick butt version.

[Nailhead]

Greg
I have three of the boosters, 3 watt output. Mine are smoothtalkers and they work real well. I also use a directional  antenna along with a booster and our camp and reach apx. 18 miles as the crow fly's over water and it works good on most days.
NH

[SwampDonkey]

I'm within 10 miles of 3 towers here and I live on a hill, just not the crest. And I can't get cell here. I can just about see one tower furthest to the north and the one tower I can see is US Cellular, no good to me. I know one forest company that if you overlap their map with the cell phone coverage map, their land is all outside coverage.  :D :D

[Corley5]

With the leaves off I can see the lights from cell towers in four different directions.  With leaves I can see them in two directions  ;)  Two are six miles away.  Others are 10 and 15.  Doesn't do me a bit of good either  : ;D  Still haven't gotten to the Alltel store

[SwampDonkey]

 :D :D :D :D :D 8)

This place reminds me sometimes of a 'barrel of monkeys'. :D

[Polly]

 8)uncle sam frowns on amplified broadcasting devices so i have heard  8)

[Rockn H]

If the external antenna doesn't help, the repeater from wilson will do the job.  With the repeater you don't have any wires to worry with and you can use more than one phone at a time.  I don't have one because unfortunately they're $400. :'(

[Buzz-sawyer]

If you like do it yourself stuff you can easily build a yagi antenna or a so called can-tenna for the 1900 or 800 bands...otherwise a yagi off of ebay can get to 24dbi gain...which is good

[Bill Johnson]

When we got rid of our bag phones and went to digital we pickup amplifiers for the trucks, that coupled with the fact there are two new towers gives us coverage in areas where we never had with the bag phones, as long as the phones are in the trucks and hooked up they work great.  Of course I still carry my satellite phone in the bush "just in case".

I'm not sure what make of amplifier we installed but know that it was around $300 CND for it then tossing in the hands free, and dash mount brought it up to close to $500, still well worth the money.