Re: Do these cellular amplifiers work for all cellphones?

On 2022-04-10 11:46, nospam wrote:
> In article <[email protected]>, Alan Browne
> <[email protected]> wrote:
> 
>>
>> The one thing that does stick out:  If there is at least a little signal
>> from the cell then the connection is improved appreciably.
> 
> the problem is that these devices must work in *both* directions.
> amplifying the signal only one way is not going to work.

1) They work because they improve bandwidth which is also a function of 
power.  The cell tower seeing more bandwidth (and less bad packets) from 
the cell phone (which still appears relatively weak at the tower), can 
respond more often with packets.  Further the cell will increase the 
power sent in that direction (as it still appears relatively weak). 
More power=more bandwidth.

2) The conditions for how they work are very non-linear.  You could be 
within working range, but if the cell can't detect the phone or v-v, 
then the connect protocol fails to get things going.

3) So when the tower is in range to get nearly the first bar, at least 
the protocol gets started, then the benefit of higher bandwidth from the 
phone to the tower (more power, more packets, less dropouts), the cell 
can respond in kind.

One of the comments on Amazon was from a hunter: "Doesn't work!  Don't 
bother!"  But of course where he was there were no towers at all.  No 
magic, alas.

Most other comments on Amazon (confirmed buyers) are quite positive with 
about 75% 5* for an expensive home unit.

For mobile (and the co. originally cited) it goes to:

44% 5*
19% 4*
12% 3*
  9% 2*
16* 1*

User expectations need to be realistic - as in all things.  And I would 
assume mobile users would be the most frustrated - for good reason.

Another issue with some units is the cell phone has to be 
unrealistically close to the "inside" antenna in the car.  (I assume 
because it has to avoid cross-talk with higher power signal).  Many kits 
want the high power antenna to be as far as possible from the 
cell/indoor unit).

-- 
"Mr Speaker, I withdraw my statement that half the cabinet are asses -
  half the cabinet are not asses."
-Benjamin Disraeli