Vile 5 wrote:
"And all the cust service responses from various cell phone antenna
sites say there is not much for 900, 1000, 1100 mhz which is what the
specs say on the phone."

That`s reasonable. Cell phones communicate with whichever base station
works best in a wide network. This is almost the ultimate space and
frequency diversity system. Antennas are low which limits range. No
problem as contact is lost it is immediately re-established
automatically with another station, the new best choice.

As azimuths between phones and bases are constantly changing,
concentrating phone energy at a articular azimuth does not make sense if
the phone is moving.

Efficiency makes sense. Concentrating energy along the horizontal makes
sense for most users.

Best regards, Richard Harrison, KB5WZI

"Richard Harrison" wrote in message
...
As azimuths between phones and bases are constantly changing,
concentrating phone energy at a articular azimuth does not make sense if
the phone is moving.

There's a lot of research going on for 'smart' antennas that effectively are
just electronically phased arrays that continuously re-tune themselves to
'lock on' to a base station. Neat idea, with the usual benefits of
potentially less power for a given range, better range for a given power,
etc., but I don't know whether or not any commercial phones employ the idea
yet.

Joel Kolestad wrote:
"There`s a lot of research going on for "smart" antennas that
effectively are just electronically enhanced arrays that continuously
retune themselves to "lock on" a base atation."

I became aware of that sort of adaptation by reading a notice from the
IEEE Houston Section of an appearance that Cecil`s old professor at
Arizona, Balinas (sp?) was going to make here to clue the locals in on
the latest developments in adaptive antennas. Unfortunately, I didn`t
go. I`ll have to learn elsewhere.

Best regards, Richard Harrison, KB5WZI

I wrote that Dr. Balanis presented recent developments in adaptive
antennas to the Houston Section of the IEEE. I apologize for misspelling
his name. I found the correct spelling in the index of the 3rd edition
of Kraus` "Antennas".

Best regards, Richard Harrison, KB5WZI

The having no port is the main problem...That means you
have to use those coupler devices that fit behind the antenna
in the phone...Unfortunately, I just had to buy a new phone,
and my new one is the same way. No port...They make a sleeve
that fits over the top, and has a patch to couple to the internal
antenna, but I have to wonder how well it works...Some reports
seem lackluster...As far as antennas, I guess it depends on
what you want...A connection to a cheap UHF TV antenna
might work ok....But most long distance house cell antennas
are yagi's that I see sold. Anything commonly used for UHF,
could be adapted to cell phone...Often on those freq's, just
moving a few feet can make a big difference...So I'd try different
locations, and try to find "hot spots"...Thats about where I would
mount the antenna if it's not going to be real high...
I'd like to find the goofball that decided these phones don't
need an antenna port.... Whatta putz....Having an outside
antenna makes a huge difference out on the interstates... MK

Richard Harrison wrote:
Vile 5 wrote:
"I would like to build a passive antenna for my cell phojne that has
no
port. I know it goes into the 1100 MHZ range if that helps."

J.D. Kraus invented an antenna in 1938 that may help. He called it a
corner reflector.

The ARRL "Antenna Book" has tables and construction details, but you
might get by by making a cardboard corner papered on its inside with
aluminum foil. to make a reflector for your cell phone. You might
make
it twice as wide as it needs to be so that you can make a 90-degree
bend
in its middle. both reflecting panels (either side of the fold) may
then
be one or two feet on a side.

You might wrap the reflector around the phone and your head while you
aim the interior angle in the direction of the repeater which serves
you
best. You may get around 10 dB gain which is enough to make a
difference
but not solve every problem. Don`t bother trying to patent the corner
reflector. Kraus and RCA did that back in 1939 or 1940, I believe.

Best regards, Richard Harrison, KB5WZI

How big should this cardboard be? I might try this. I bought some
cheap tv antenna rabbit ears and got a minimum signal to check
messsages in my basement. What actually is the antenna inside my cell
phone anyway? I just need a larger version of that maybe?

Vile 5 wrote:
"How big should this cardboard be?"

You want a metal corner between squares, 1 or 2 feet on a side. It makes
a reflector in which images align with the cell phone antenna.

Best regards, Richard Harrison, KB5WZI

That url above does not have the item you ordered. Did you mean to
paste this one:
http://www.cell-phone-accessories.com/moc6cephanbo.html

The above one has Motorola C650 antenna that does not require a port on
the phone. It attaches to the back of the phone with velcro attachment.
That should solve your no-port problem and give better reception up
yonder.

This site has come up with this antenna to counter that no-port
problem. It does not require an antenna port:
http://www.cell-phone-accessories.com/moc6cephanbo.html

This means that it is good for any phone.

Send me $29.95 and DON'T buy one... everyone will think you are a fool for
sending me the money--but at least they won't think you a fool for buying
that junk...

Warmest regards,
John

"jamison" wrote in message
oups.com...
This site has come up with this antenna to counter that no-port
problem. It does not require an antenna port:
http://www.cell-phone-accessories.com/moc6cephanbo.html

This means that it is good for any phone.