Trying to build an antenna for cell phone
 

Thought I would start here for this question. I would like to build a
passive antenna for my cell phone that has no port. I know it goes
into the 1100 MHZ range if that helps. I would like to use this for
using in my house and for car use. Unless you know of a good link to a
site that sells such a thing. It seems like every new cell phone I get
over the years never has the range that is needed to pick up the towers
in my home (upstairs) or in my car over country roads (drops calls).

Thanks

On 20 Apr 2005 04:56:21 -0700, wrote:

Thought I would start here for this question. I would like to build a
passive antenna for my cell phone that has no port. I know it goes
into the 1100 MHZ range if that helps. I would like to use this for
using in my house and for car use. Unless you know of a good link to a
site that sells such a thing. It seems like every new cell phone I get
over the years never has the range that is needed to pick up the towers
in my home (upstairs) or in my car over country roads (drops calls).

Thanks

try http://www.ccrane.com

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 about this, just change the dimensions for the frequency you wish to
cover?
http://martybugs.net/wireless/biquad/
Seems like decent gain for a simple design...
Regards,
John

wrote in message
oups.com...
Thought I would start here for this question. I would like to build a
passive antenna for my cell phone that has no port. I know it goes
into the 1100 MHZ range if that helps. I would like to use this for
using in my house and for car use. Unless you know of a good link to a
site that sells such a thing. It seems like every new cell phone I get
over the years never has the range that is needed to pick up the towers
in my home (upstairs) or in my car over country roads (drops calls).

Thanks

I don't think I can build this. Are the parts avail on that site? I
did find a interesting item I ordered on ....

http://www.cell-phone-accessories.com/link.html. Motorola c650.

if it works I will report back or if it does not for that matter.

You are joking, right? puzzled-look-on-face

Regards,
John

Well this does seem better so far, but could be better. I went to
Menards and went to the long metal pipe section and had full bars
there. Makes me just want to find a portable long antenna that is
colaspable since I can't drive around with a long metal pipe in
my car.

Ahhh, I can see this question is out of my league, I am a newbie--the
old-timers can probably put ya straight wink

Regards,
John

John Smith wrote:
"I can see this question is out of my league."

Or, out of his parallel universe.

Best regards, Richard Harrison, KB5WZI

I would like to build my own, I just need to figure out where to get
the parts from. Again I did not see any thing on that site so far.
The one I bought so far does not seem to make too big a dif so far.
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. And yes I am a layman for this but willing to
learn what I can if only for the knowledge.

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.

Comon, now - The image is crappy but that velcro antenna may be a good
idea for those phones that do not have an external antenna port.
Enlighten me about why you think it is junk. I mean, I would really
like to know if you care to elaborate just a tad bit more to support
your argument. Thanks.

Well, if you have worked with antennas at all, you would know why...

.... but then, even sugar pills (placebos) cure illnesses... and in that
sense--could just work!

I mean, I go to extremes to attempt to keep an open mind... that cell
antenna even closes my mind... frown

Warmest regards,
John

"jamison" wrote in message
oups.com...
Comon, now - The image is crappy but that velcro antenna may be a good
idea for those phones that do not have an external antenna port.
Enlighten me about why you think it is junk. I mean, I would really
like to know if you care to elaborate just a tad bit more to support
your argument. Thanks.

If You can drill a hole in Your motorola's plastic enclosure
(it's probably removable so You can have one for replacement)
probably there will be 50OHm port inside.
When they test phones - all have to be connected with measuring
equipment - directly feed through 50Ohm cable /there are some
situations that producer prepares "test fixture" which looks just
like small patch antenna mounted on the phone/. Anyway - even on
nokia 3650 (this model has internal tri-band patch antenna)- when You
remove front panel - there is a connector - to simplify test setups.

Greetings
Andrzej Rusiecki

jamison wrote:

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.

Yea, I've seen that. They also make a "sleeve" version
which is a perfect match for my nokia phone. I just wonder
how well they actually work...Actually, I would prefer to make
one myself, but I'm not sure how I would want to go about it..
IE: would I need a resonant 800 mhz "coupling antenna", etc..
I tried just making a experimental patch out of foil, and sticking
it on the back, behind the internal antenna, but it didn't seem to
work.. Anyone have any good ideas how to homebrew one?
Actually, I've also been considering just drilling a hole in the phone,

and installing a antenna port....
MK

Send me $29.99 and I'll send you the plans and a roll of aluminum foil with
some copper tape... grin

Warmest regards,
John
wrote in message
ups.com...
Yea, I've seen that. They also make a "sleeve" version
which is a perfect match for my nokia phone. I just wonder
how well they actually work...Actually, I would prefer to make
one myself, but I'm not sure how I would want to go about it..
IE: would I need a resonant 800 mhz "coupling antenna", etc..
I tried just making a experimental patch out of foil, and sticking
it on the back, behind the internal antenna, but it didn't seem to
work.. Anyone have any good ideas how to homebrew one?
Actually, I've also been considering just drilling a hole in the phone,

and installing a antenna port....
MK

Dave:

Interesting design, can't wait to show this to the 2.4 Ghz guys here...
simple, eloquent and even looks like it will work!!!

Warmest regards,
John

"DaveC" wrote in message
news.net...
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?

Here's a cut-out template parabolic reflector. Works for all frequencies.
Uses cardboard and aluminum foil (from the kitchen):

http://www.freeantennas.com/projects...te2/index.html

Good luck,
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC

This is an invalid return address
Please reply in the news group

On Wed, 25 May 2005 15:30:31 -0700, nm5k wrote:

Yea, I've seen that. They also make a "sleeve" version
which is a perfect match for my nokia phone. I just wonder
how well they actually work...Actually, I would prefer to make
one myself, but I'm not sure how I would want to go about it..
IE: would I need a resonant 800 mhz "coupling antenna", etc..
I tried just making a experimental patch out of foil, and sticking
it on the back, behind the internal antenna, but it didn't seem to
work.. Anyone have any good ideas how to homebrew one?
Actually, I've also been considering just drilling a hole in the phone,

and installing a antenna port....
MK

Check the Nokia Web site, most, but not all, phones have an antenna
coupler option available.



--
Korbin Dallas
The name was changed to protect the guilty.