Coax cable for Wi-Fi PCI Adapter

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Is there a source of pre-cut and terminated coax cable from whom
I can buy a short piece of coax to let me move the antenna on my
wife's computer out of the shadows?

Her computer is located in a cubby hole in the hallway, and the
CPU has to be oriented such that the Linksys WIreless-G WMP54G
PCI Adapter is in the shadow of the CPU box, relative to the
WI-FI Access Point.

I want to buy a short piece of coax cable with terminals that
will fit this Wi-Fi adapter and let me place the antenna above
the CPU box. I could locate it in the shelves above her computer,
and hopefully get a much stronger signal level to/from the Access
Point.

Do I need a coax cable with RP-TNC terminals or is this not
compatible with the Linksys adapter?

Re: Coax cable for Wi-Fi PCI Adapter




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There is a thread titled "Cheap wifi antennas" on 6/19/06 that you should go
back to read, that card has a RP-SMA connector.
 http://www.hyperlinktech.com/web/cable_radio_pigtails_switchcase.php?connection=RP-SMA&pgType=rp-smaI
like panel antannas because they are
directional.http://www.hyperlinktech.com/web/antennas_2400_in.php


Re: Coax cable for Wi-Fi PCI Adapter



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http://www.hyperlinktech.com/web/cable_radio_pigtails_switchcase.php?connection=RP-SMA&pgType=rp-smaI
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Sorry, the spacing in the above links made the links unuseable. I will
repost

There is a thread titled "Cheap wifi antennas" on 6/19/06 that you should go
back to read, that card has a RP-SMA connector.
http://www.hyperlinktech.com/web/cable_radio_pigtails_switchcase.php?connection=RP-SMA&pgType=rp-sma

I like panel antannas because they are directional.
http://www.hyperlinktech.com/web/antennas_2400_in.php
 



Re: Coax cable for Wi-Fi PCI Adapter


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A few.  I find http://www.hyperlinktech.com has nice listings, but a
minimum $100 order.    Look under Cables & Pigtails.

http://www.fab-corp.com/ sells at retail, and might be able to help you
identify the antenna that you need.

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An astute observation for a common situation.  I would say that's RP-SMA, a
very common connector.

A few people have done that with some success.  Someone added a reflector
to the stock antenna at the same time:
http://homepages.picknowl.com.au/gloaming_agnet/info.html
Jeff Liebermann suggests that there is something not quite right with this
photo, but the concept is good.  The antenna here is an EZ-10 from
http://www.freeantennas.com .  (I would have used the EZ-12, myself)
http://www.rahul.net/dold/clarence/EZ12-windsurfer.jpg

But, oddly enough, for the price of the chunk of cable, you might be able
to buy a directional antenna.  I have used the "Hawking HAI6SDA Directional
6dBi 2.4GHz Antenna" with good success on a Netgear WG311 PCI card.
$20-30.
<http://www.hawkingtech.com/products/productlist.php?CatID=32&FamID=58&ProdID=122
The one I bought fit the Netgear, and had an adapter that fit RP-TNC.

--
---
Clarence A Dold - Hidden Valley Lake, CA, USA  GPS: 38.8,-122.5

Re: Coax cable for Wi-Fi PCI Adapter



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<http://www.hawkingtech.com/products/productlist.php?CatID=32&FamID=58&ProdID=122
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I bought one a hawking antenna this weekend on sale for 10 bucks at Fry's
(normally 20) .  It raised the signal strength from 2 bars to 5.  I was
amazed.  Of course ymmv.

Dennis



Re: Coax cable for Wi-Fi PCI Adapter



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Sure.  It's called a coax "jumper".

See:
  http://www.fab-corp.com/home.php?cat=249
 http://www.wlanparts.com/c=7LAEdsyLb2FOUiR1fWEiIomCj/category/cables /
Oops.  No RP-TNC to RP-TNC jumper.
  http://www.hyperlinktech.com/web/cable_feed.php

You'll need to decide what length cable you need, and what diameter
coax is appropriate.  A good rule of thumb is that 6dB coax loss is
good for cutting your range in half.  Roughly, the losses for common
small diameter coax cables are:
  Coax     loss/ft
  RG-174    .75
  RG-316    .38
  LMR-100   .23
  LMR-240   .13
I would keep the total attenuation down below 3dB if possible.
  
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As Clarence Dold suggested, you can get a better directional antenna
with coax cable extension, for about the price of just the extension.
The stock rubber ducky antenna is NOT a very wonderful antenna (2dBi
gain at best).  For a fixed location pointing at one access point,
directional antennas are always a better idea.

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Linksys uses RP-TNC for their access points.  However, the WMP54G PCI
card uses RP-SMA to conserve space.  Therefore, you need need either
an RP-SMA extension cable, or a replacement antenna plus cable.

--
Jeff Liebermann     jeffl@comix.santa-cruz.ca.us
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

Re: Coax cable for Wi-Fi PCI Adapter


Gordon wrote:
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Linksys have an SMA RP connector on the PCI card, I have a linksys
WMP54GS myself.  Try the antenna base from here:
http://www.wifi-antenna.co.uk /

If you can mount the router away from walls (inc stud) you should be OK.

My PC is tucked into a little cubby and I had a signal strenth of
between 38% and 54%.  I bought one myself and the signal improved by
over 1/3 and I typically got 68% - 78%.   Cable is 1m long but they dose
cable by the meter as well.

Service is excellent BTW and he sells antenna as well if you want to
upgrade.

I have a WRT54GS router and upgrading the firmware made a lot of
difference.  I use channel 13 (prev had 11 channels) and get mid 90s
reception.  I don't use the linksys software, XP manages the connection
and I find I have almost no breaks in the connestion.  With he linksys
drivers I would have short breaks in the connestion which were annoying.
  It seemed to be renewing the association with the router when the
connection was idle.

Mike

Re: Coax cable for Wi-Fi PCI Adapter


On Sat, 24 Jun 2006 15:30:06 GMT, Gordon

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Thanks to all who responded. I bought a 7 foot long Cantenna
Antenna Extension Cable at CompUSA and placed it between the
Wi-Fi card and its antenna. This lets me position the antenna in
a clear area. It works very well and I consider the problem
solved.

This cable has RPSMA male and female connectors that match my
LinkSys WMP54G PCI Adapter. This has boosted the signal to a very
usable level of around 54% and it seems very steady. I even
picked up another wireless network SSID that seems to be coming
from two houses down the street. I didn't try to log onto this
network, but I will talk with the owner and let them know that
they are open.

Re: Coax cable for Wi-Fi PCI Adapter



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may i ask how you know it is two houses away ??





Re: Coax cable for Wi-Fi PCI Adapter


On Sun, 25 Jun 2006 20:07:05 GMT, "aussie bongo"

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I've gone through a process of elimination with all the closer
houses. Of course it might be from a greater distance...who
knows?


Re: Coax cable for Wi-Fi PCI Adapter


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Why?  They may actually want to leave it open, if only to let other folks
share the bandwidth.

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Could be something obvious like an SSID labelled "Smith" and knowing the
Smith's live two doors down.  I found one in our marina, let's say it was
named "Finch".  I searched for that last name, in the current zip code, on
switchboard.com.  I noticed there was someone with that last name listed at
an address that had a pretty good line of sight to the marina.  Thus it's
reasonable to conclude they're one and the same.  Same deal goes at home,
there's an SSID with the same name as a neighbor's teenager.  Not all that
hard to figure out.

-Bill Kearney


Re: Coax cable for Wi-Fi PCI Adapter



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Obvious doesn't always work.  My systems have the street address of
the access point as the SSID.  No way to miss something that obvious.
While installing a pair of WAP54G bridge radios in downtown Santa Cruz
last week, I noticed someone walking around with a PDA and a small
panel antenna.  He was blundering around the street outside the store
where I was working.  He turned out to be someone I had exchanged
email on a local wireless mailing list, but I had never met in person.
He was trying to build a map of local Wi-FI installations and was
having trouble finding the one I was currently installing.  I pointed
out that the SSID was the address, which aparently escaped his notice.

Moral:  Obvious is not always sufficient.

--
Jeff Liebermann     jeffl@comix.santa-cruz.ca.us
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

Re: Coax cable for Wi-Fi PCI Adapter


On Tue, 27 Jun 2006 08:54:25 -0700, Jeff Liebermann

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A great many people, when they see something that obvious, tend
to think it is a trick devised to mislead the gullible.

My guess about the signal coming from the second house down the
street was based on the fact that I've touched base with everyone
in the houses adjacent to mine, and it ain't none o' them. The
second house down the street is the only other one that could
send a signal to my house without having to pass through some
very heavy tree foliage. But, I still haven't gone down there and
talked with the owners/occupants of that house. This signal is
WEP encrypted, so I doubt they intend to offer their Wi-Fi as a
free neighborhood service.

There really isn't much danger of encroachment in this
neighborhood, although it could happen anywhere, I guess. Most of
my neighbors don't even know what Wi-Fi means.

Re: Coax cable for Wi-Fi PCI Adapter


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When you make something idiot-proof, the world goes and builds a better
idiot.


Re: Coax cable for Wi-Fi PCI Adapter



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This was a recent university graduate so I'll assume that idiocy is
not the problem.  The problem is that obvious clues are not so obvious
if one is not expecting them.  Trying to decode SSID's and guess their
owner has been somewhat of a challenge.  With the time honored
practice of security by obscurity, SSID's tend to be rather obscure
and cryptic.  When someone runs across one that is clear, concise, and
obvious, it's often lost in the noise.  Also, he was using a PDA
running Kismet, were the on screen display is rather difficult to
read.  He apparently didn't notice that the SSID was the address and
was mentally trying to decode the meaning when I interrupted.

Incidentally, in the past, I did some work with RFC3825.
RFC 3825 - Dynamic Host Configuration Protocol Option for
Coordinate-based Location Configuration Information
  http://www.faqs.org/rfcs/rfc3825.html
  http://www.iana.org/assignments/bootp-dhcp-parameters
It's primary use is for E911 caller location via 802.11 VoIP phones.
The access point is pre-loaded with the latitude, longitude, and
altitude/floor number (LCI).  Clients using the access point obtain
their location via DHCP.  When making an emergency call, the stored
location is then communicated to the PSAP (public safety access
point).


--
Jeff Liebermann     jeffl@comix.santa-cruz.ca.us
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

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