T&T: A Cell Phone Amplifiers

[George Hechtman]

I'll look at these at next week's Consumer Electronics trade show,  
and consult with my old colleagues. As I recall, this Wilson piece is  
an in-vehicle (that is a car) unit and is designed to cover an area  
that size. The description appears to confirm that. We had no luck  
adapting these vehicle units to bigger spaces. By limiting the  
coverage area, they mitigate the problem of cross-talk between the  
external and internal antennas (further helped by the use of the  
car's metal roof acting as a ground plane and shield).

The general problem with the wireless cellular systems on FRP boats  
is the lack of shielding (or ability to get enough vertical and  
overall separation)twixt the two antennas. This cross talk renders  
the system either completely useless (and sometimes damaged) or just  
too weak to be worth it. A highly directional, properly positioned  
interior antenna can help offset this in smaller boats. Right-sizing  
the system to the space you will be covering is important.
On most boats, especially with the advent of any number of Bluetooth  
handsfree options, I just don't see a big payoff, unless you will  
have numerous cell devices active at once. And even then, it doesn't  
work on the flying bridge or most exterior spaces.

Properly configured cellular wireless booster systems do co-exist  
fine with wi-fi systems. At CES, one of the things I'll be looking  
for is something like the Lynksys that has USB capability. We played  
around with some units this past spring from a few companies, with  
inconsistent results.

Just to reiterate, my old company has sold/deployed thousands of  
these cellular systems, wired and wireless, into a very wide variety  
of environments. We had real engineers using real test equipment  
assisting really picky customers including government entities, law  
enforcement, oilfield (offshore and land) service companies, etc. So  
any comments I have on the subject aren't just based on "I tried one  
of them once in my marina and it didn't seem so good". Which of  
course may well end up being the case in any one individuals  
circumstance.

George

On Jan 3, 2008, at 6:26 AM, Dave Clark wrote:

> George Hechtman Wrote: (big Snip)
> Gee, another topic I have some bit of expertise in. I come from the
> cellular and mobile electronics industry, my old company is a
> wholesale distributor and resell of a range of these products. See
> archives for previous writings. We sold and installed a wide variety
> of both wired and wireless systems. In the consumer/small business
> arena, Wilson and Digital Antenna (DA), with the vast preponderance
> of sales in the latter.
> George
>
> I use two phones plus an aircard on AT&T. I have already installed  
> the Wilson marine antenna and am interested in how to best complete  
> a system for the boat.
> I'm looking at the Links Wireless-G Router for Mobile Broadband  
> part number WRT54G3G-AT:
> http://www.cdw.com/shop/products/default.aspx?EDC=1281958
> and the Wilson 801201 wireless amplifier:
> http://www.pricegrabber.com/user_sales_getprod.php? 
> masterid=16572172&lot_id=2717136
>
> I believe these would work together if I put the aircard in the  
> Linskys and the outside antenna on the amp, use the "stealth"  
> antenna with the amp as provided by Wilson. So both units and the  
> phones would work wirelessly.  Am I missing something? Is there  
> something about the wireless that doesn't work well on a boat? It  
> seems simple enough but I don't want to put out a lot of money to  
> "test" a system that is known to have problems.
>
> Dave and Marcy Clark
> ADAGIO
> 1983 President 41
> Lying Grand Mariner Marina
> Mobile, AL