Cheap wifi antennas

Hi all,

Just upgraded the stock (2db?) antenna on the back of the Pc witha better one..
(9db)

Cheap as chips.. so I thought I'd share the site: www.wifi-antennas.co.uk

Doz <(E-Mail Removed)> wrote:

> Just upgraded the stock (2db?) antenna on the back of the Pc witha better
> one.. (9db)

> Cheap as chips.. so I thought I'd share the site: www.wifi-antennas.co.uk

www.freeantennas.com

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

On Mon, 19 Jun 2006 09:56:37 +0100, Doz <(E-Mail Removed)> wrote:

>Just upgraded the stock (2db?) antenna on the back of the Pc witha better one..
>(9db)

Let me see if I understand what you've done. You replaced the stock
2dBi rubber ducky antenna with a bigger rubber ducky antenna that
claims 9dBi. Well, a vertical colinear with 9dBi gain would be about
400mm long. Close enough:
http://www.allendale-hosting.co.uk/antenna/9dbi.htm

However, there are a few problems. Both antennas are far too close to
the metal case of the computer to not have the case interfere with the
pattern, VSWR, and mechanical mounting. The case acts as a shield. So
does the traditional tangle of wires behind most PC's. In addition,
most PC's seem to live under a table, on the floor, or buried inside a
cabinet, which are not the best RF locations.

What you should have bought is a lower gain antenna with a length of
coax cable terminated by an RP-TNC. That will position the antenna
away from the metal box, tangle of wires, and miserable location.
Something like the antenna base at:
http://www.allendale-hosting.co.uk/antenna/base.htm
Unforunately, this uses the stock 2dBi antenna. It would be nice if
the antenna had some gain to compensate for the coax cable loss. So,
a better combination would be:
http://www.dlink.com/products/?sec=1&pid=416
http://www.dlink.com/products/?sec=1&pid=325
There are other combinations.

>Cheap as chips.. so I thought I'd share the site: www.wifi-antennas.co.uk

Share the results instead. How much farther or better can you go with
the new antenna?

--
# 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

Jeff Liebermann <(E-Mail Removed)> wrote:
> What you should have bought is a lower gain antenna with a length of
> coax cable terminated by an RP-TNC. That will position the antenna
> away from the metal box, tangle of wires, and miserable location.

Or the freeantennas variant, with a chunk of coax:
http://homepages.picknowl.com.au/glo...gnet/info.html
I think this was reported in the thread "EZ10 antenna results" a week ago
in this newsgroup.

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

(E-Mail Removed) hath wroth:

>Jeff Liebermann <(E-Mail Removed)> wrote:
>> What you should have bought is a lower gain antenna with a length of
>> coax cable terminated by an RP-TNC. That will position the antenna
>> away from the metal box, tangle of wires, and miserable location.
>
>Or the freeantennas variant, with a chunk of coax:
>http://homepages.picknowl.com.au/glo...gnet/info.html
>I think this was reported in the thread "EZ10 antenna results" a week ago
>in this newsgroup.

Yeah, I saw that. Very clever. However, I noticed something odd. The
sex of the connectors don't make sense. The antenna is probably a
common RP-SMA. The right angle connector on the cable can be either
SMA or RP-SMA. However, the barrel adapter doesn't make sense. I've
never seen an RP-SMA to RP-SMA barrel, and certainly not an RP-SMA to
SMA barrel. Looking at the area between the barrel and right angle
SMA, there's far too much thread exposed for a proper fit. Something
odd about this connector derrangement.

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

On Tue, 20 Jun 2006 06:08:13 GMT, Jeff Liebermann
<(E-Mail Removed)> wrote in
<(E-Mail Removed)>:

>On Mon, 19 Jun 2006 09:56:37 +0100, Doz <(E-Mail Removed)> wrote:
>
>>Just upgraded the stock (2db?) antenna on the back of the Pc witha better one..
>>(9db)
>
>Let me see if I understand what you've done. You replaced the stock
>2dBi rubber ducky antenna with a bigger rubber ducky antenna that
>claims 9dBi. Well, a vertical colinear with 9dBi gain would be about
>400mm long. Close enough:
> http://www.allendale-hosting.co.uk/antenna/9dbi.htm
>
>However, there are a few problems. Both antennas are far too close to
>the metal case of the computer to not have the case interfere with the
>pattern, VSWR, and mechanical mounting. The case acts as a shield. So
>does the traditional tangle of wires behind most PC's. In addition,
>most PC's seem to live under a table, on the floor, or buried inside a
>cabinet, which are not the best RF locations.
>
>What you should have bought is a lower gain antenna with a length of
>coax cable terminated by an RP-TNC. That will position the antenna
>away from the metal box, tangle of wires, and miserable location.
>...

My own preference would be a USB Wi-Fi adapter, which makes it easy to
position the adapter properly without any signal loss. High-end unit:
<http://www.ccrane.com/antennas/wifi-antennas/super-usb-wifi-antenna.aspx>
Assuming the specs aren't fantasy. Here's another:
<http://www.radiolabs.com/products/wireless/waverv.php>
Or Hawking HWU8DD
<http://www.hawkingtech.com/products/productlist.php?CatID=32&FamID=60&ProdID=280>

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

John Navas <(E-Mail Removed)> hath wroth:

>My own preference would be a USB Wi-Fi adapter, which makes it easy to
>position the adapter properly without any signal loss. High-end unit:
><http://www.ccrane.com/antennas/wifi-antennas/super-usb-wifi-antenna.aspx>

20dBm (sic) of omni gain from a 1ft long antenna? No way.
Typical 5dB (sic) antenna found on a standard router? Try about 2dBi
and what's a "standard" router?
Price is $120.

>Assuming the specs aren't fantasy. Here's another:
><http://www.radiolabs.com/products/wireless/waverv.php>

802.11b only. The claimed 15x range improvement would require an
antenna gain of about 23dBi[1]. No way with that small an omni
antenna.
Price is $170

>Or Hawking HWU8DD
><http://www.hawkingtech.com/products/productlist.php?CatID=32&FamID=60&ProdID=280>

Price is $62. I ran the numbers previously on the antenna and it
apparently really does have 8dBi gain.

The two Dlink antennas I suggested are $44 and $24 respectively. Think
cheap.

[1] Range doubles for every 6dB of gain increase.
Range gain power gain
incr. (dB) (linear)
2x 6 4x
4x 12 16x
8x 18 63x
16x 24 251x
32x 30 1000x

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

On Tue, 20 Jun 2006 22:20:47 -0700, Jeff Liebermann
<(E-Mail Removed)> wrote in
<(E-Mail Removed)>:

>John Navas <(E-Mail Removed)> hath wroth:
>
>>My own preference would be a USB Wi-Fi adapter, which makes it easy to
>>position the adapter properly without any signal loss. High-end unit:
>><http://www.ccrane.com/antennas/wifi-antennas/super-usb-wifi-antenna.aspx>
>
>20dBm (sic) of omni gain from a 1ft long antenna? No way.
>Typical 5dB (sic) antenna found on a standard router? Try about 2dBi
>and what's a "standard" router?
>Price is $120.

Perhaps the gain figure is being artificially boosted by amplification
(as compared to standard products). FWIW, C.Crane is considered to be a
fairly reputable outfit. Still, I'd probably go for the Hawking
product.

>>Or Hawking HWU8DD
>><http://www.hawkingtech.com/products/productlist.php?CatID=32&FamID=60&ProdID=280>
>
>Price is $62. I ran the numbers previously on the antenna and it
>apparently really does have 8dBi gain.

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

Jeff Liebermann <(E-Mail Removed)> wrote:
> What you should have bought is a lower gain antenna with a length of
> coax cable terminated by an RP-TNC. That will position the antenna
> away from the metal box, tangle of wires, and miserable location.

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>

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

John Navas <(E-Mail Removed)> hath wroth:

>On Tue, 20 Jun 2006 22:20:47 -0700, Jeff Liebermann
><(E-Mail Removed)> wrote in
><(E-Mail Removed)>:
>
>>John Navas <(E-Mail Removed)> hath wroth:
>>
>>>My own preference would be a USB Wi-Fi adapter, which makes it easy to
>>>position the adapter properly without any signal loss. High-end unit:
>>><http://www.ccrane.com/antennas/wifi-antennas/super-usb-wifi-antenna.aspx>

>>20dBm (sic) of omni gain from a 1ft long antenna? No way.
>>Typical 5dB (sic) antenna found on a standard router? Try about 2dBi
>>and what's a "standard" router?
>>Price is $120.

>Perhaps the gain figure is being artificially boosted by amplification
>(as compared to standard products). FWIW, C.Crane is considered to be a
>fairly reputable outfit. Still, I'd probably go for the Hawking
>product.

Perhaps the product description is somewhat incoherent? Just about
every term in the short product description is misused. 20dBm is
probably the transmit power, although it's difficult to deduce from
the description. I hadn't seen the term "range booster" applied to a
USB wireless client, but I guess someone has to be first in the
creativity department.

The concept of a suction cup, stick on window, USB radio with an omni
antenna is rather interesting. Similar integrated USB radio/antenna
combinations usually use a patch or panel antenna. The idea of
putting it in the window is usually to be able to hit a remote access
point, where antenna gain is most important. With a directional gain
antenna, inside coverage is usually of no interest. However, an omni
in the window offers the worst of both worlds. The omni has much less
antenna gain for hitting remote access points. Located in the window,
it will pickup more interference from the outside, making it a rather
odd choice for indoor coverage. In other words, an omni in the window
doesn't make much sense.

I will admit that it's a rather clever method of mounting. It's
described as "... the best indoor, Mobile or RV WiFi antenna made".
Most RV's have window screens which might be metal. I guess this
might work in a vehicle if the windows aren't coated with metalized
mylar and are fairly vertical. Indoor coverage is a problem because
of the outside interference problem, but also because the spacing
between the antenna and whatever it's stuck to is insufficient to
prevent interaction. For example, sticking it on a metal refrigerator
is probably a bad idea unless the spacing is about 1/4 wavelength,
making the fridge into an improvised reflector.

The total lack of specs and relatively high price makes me rather
suspicious. The device seems to labeled "Fly High" which is probably
the product name, not the manufacturers name. I couldn't find
anything in the FCC ID data pile, Wi-Fi certifications, or with
Google. Looks like they have an exclusive on this one.

I've never bought anything from Bob Crane, but agree that he seems
reputable. It's not listed in the current printed catalog or on any
of the "new products" web pages. My guess is that this is a very new
product, with zero documentation, that was rushed to the web page in
great haste. I suspect the description will be fixed and spec
supplied after the questions come in from prospective buyers.

Incidentally, the name "SUPER USB WIFI ANTENNA" kinda turns me off.
Anything super, amazing, magic, miracle, turbo, enhanced, and
ultimate, rarely lives up to the superlative.

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