Best wireless card for external antenna

My knowledge in wireless networking is next to nothing, except for what
I have read here and from many of the links you have posted. I'm
hoping to gain access to the AP at my employer which is located 1/4
mile away from my home. I don't have a clear LOS, but from the attic
I should only have to go through a few other houses' attics and one
window so maybe it will work.

Here is what I have thought about.

1) Building a biquad antenna like this one:
http://martybugs.net/wireless/biquad/ and find a good place for it at
the attic.

2) Then connecting the antenna to the desktop PC with 25' low loss
coax cable, probably LMR-400. 25' should give a signal loss of just
1.7dB.

3) Choosing the wireless adapter is the hardest part. I have been
browsing through newegg and read many reviews. People seem to have few
problems with the D-Link DWL-AG 530, so based on this, it may be a safe
buy for a beginner. It has a little external antenna which is
detachable. Does anyone know which connector this card has? I have
checked D-link's website but they don't seem to tell anything about
this.

But would this adapter be the optimal for this setup? Or is there
anything better out there, perhaps more suitable for long distance
hook-ups? Speed is not the most important but I'll like to have a
fairly reliable connection.

And what about lightning storms? Would you protect a network card which
has 25' cable mounted? I know how induction from lightning can kill
electronics.

I appreciate all your feedback.

On 19 Jun 2006 00:29:32 -0700, "time4me2write"
<(E-Mail Removed)> wrote:

>My knowledge in wireless networking is next to nothing, except for what
>I have read here and from many of the links you have posted. I'm
>hoping to gain access to the AP at my employer which is located 1/4
>mile away from my home.

I presume you have permission to do this from the employer.

>I don't have a clear LOS, but from the attic
>I should only have to go through a few other houses' attics and one
>window so maybe it will work.

That will take a major miracle. 2.4GHz does not like obstructions. It
really depends on from what the roofs are made. If they're extremely
thin shake or shingle, it just might work. Dry wood is fairly opaque
to 2.4GHz. However, if it's composition shingle, concrete, rock, or
something that will block RF, forget it.

>Here is what I have thought about.

It takes two to tango. If the access point at your employers
establishment uses the stock rubber ducky antenna, and is located in a
inside office, you don't have a change. Such antennas on access
points allegedly have 300ft range, but that's under totally ideal
conditions (including no interference). You're trying to go 5 times
as far, and through several obstructions. Basically, it's not going
to happen unless you have a directional antenna at both ends, and your
employer cooperates by installing either a 2nd access point on the
roof, or re-locates the existing access point some place that's
conveninient for your wireless link.

Lacking any useful models and numbers, I can't do the antenna calcs
for you. See:
http://wireless.wikia.com/wiki/Wi-Fi#Link_Calculations
and try running the link calculations. Figure on a very optimistic 10
loss going through each roof. Aim for 20dB fade margin. If you have
problems, post your calcs and equipment list, and I'll see what can be
done.

>1) Building a biquad antenna like this one:
>http://martybugs.net/wireless/biquad/ and find a good place for it at
>the attic.

Probably not enough gain.

>2) Then connecting the antenna to the desktop PC with 25' low loss
>coax cable, probably LMR-400. 25' should give a signal loss of just
>1.7dB.

Ummm.... LMR-400 has a loss of 7.8dB/100ft. 25ft has a loss of
2.0dB. Add 0.5dB of loss for each connector pair, for a loss of 3dB
or half your power lost in the coax.

>People seem to have few
>problems with the D-Link DWL-AG 530

Sorry, not familiar with this device. What you shoudl be looking for
is a wireless client bridge or game adapter that allows an external
antenna. The radio should be mounted in the attic along with the
antenna (which will probably need to be a big dish antenna). That
will eliminate the coax cable loss. Setup some kind of power over
ethernet system to run the radio. My current favorite is either a
Linksys WET54G or WRT54G running DD-WRT firmware.

>And what about lightning storms? Would you protect a network card which
>has 25' cable mounted? I know how induction from lightning can kill
>electronics.

True. There are CAT5 lightning arrestors. Most cost more than the
wireless bridge. See thread:
| http://groups.google.com/group/alt.i...632fa4fca16576

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558 (E-Mail Removed)
# http://802.11junk.com (E-Mail Removed)
# http://www.LearnByDestroying.com AE6KS

time4me2write wrote:

> But would this adapter be the optimal for this setup? Or is there
> anything better out there, perhaps more suitable for long distance
> hook-ups?

You want to use something like the Buffalo WLI-TX4-G54HP, see
"http://www.buffalotech.com/products/product-detail.php?productid=118&categoryid=29"

You want this mounted in a weatherproof box, outside, as close to the
antenna as possible. You will run power and CAT5 cable to the box. You
cannot run an antenna from a PCI wireless adapter to an antenna far from
the card, as you'll lose too much signal in the antenna cable.

Of course even will all this, it probably won't work, unless the other
side has a similar antenna set-up, and even then it's iffy.

Thanks for your answers. I better forget the 25 ft antenna cable. I
like the idea of running the ethernet up near the antenna and
converting it to wireless and just using a short antenna cable. I think
I'll try the Buffalo Ethernet Converter that SMS suggested.

Jeff may be right about the attic not going to work. If not I will
mount an antenna on the roof. 6 ft. above will give me a LOS to the
window where the AP is located.

I forgot to mention that I can connect with a laptop from a few places
in the attic if it's not raining. Signal is very poor but it's
there, and I can log on to the network.

Thank you for your suggestions.

On 20 Jun 2006 13:18:38 -0700, "time4me2write" <(E-Mail Removed)>
wrote in <(E-Mail Removed). com>:

>Thanks for your answers. I better forget the 25 ft antenna cable. I
>like the idea of running the ethernet up near the antenna and
>converting it to wireless and just using a short antenna cable. I think
>I'll try the Buffalo Ethernet Converter that SMS suggested.
>
>Jeff may be right about the attic not going to work. If not I will
>mount an antenna on the roof. 6 ft. above will give me a LOS to the
>window where the AP is located.
>
>I forgot to mention that I can connect with a laptop from a few places
>in the attic if it's not raining. Signal is very poor but it's
>there, and I can log on to the network.

Then a directional antenna in the same location will probably work.

--
Best regards, FAQ for Wireless Internet: <http://Wireless.wikia.com>
John Navas FAQ for Wi-Fi: <http://wireless.wikia.com/wiki/Wi-Fi>
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Fixes to Wi-Fi Problems: <http://wireless.wikia.com/wiki/Wi-Fi_Fixes>

SMS,

I'm a little confused about what connecter type there should be on
the antenna cable for mounting it on the Buffalo ethernet adapter?

Could you please tell me this?

Thank you in advance.