[gentoo-user] {OT} Laptop wifi find more than external antenna
Grant
http://www.newegg.com/Product/Product.aspx?Item=N82E16833164110
Lately I've noticed there are some APs that my laptop's internal wifi
connects to perfectly, but the external antenna can't find whatsoever,
even after a lot of directional experimentation. I've tried 2
different USB dongles with the same result. Has anyone had a similar
experience? I'm baffled because the external antenna is able to make
strong connections to some APs, but it can't even find others that the
laptop's internal card finds and connects to no problem.
- Grant
James Ausmus
Maybe the USB dongle doesn't support as many bands as the internal WiFi? eg. Dongle is B/G only, while internal is A/B/G?
-James
Grant
That's a good idea, but I'm actually able to pick up the difficult
AP's with the same dongle when its normal omnidirectional antenna is
attached instead of the strong directional one. Could a failing
antenna exhibit this behavior?
- Grant
Stroller
On 8 Jan 2010, at 15:49, Grant wrote:
> ...
> That's a good idea, but I'm actually able to pick up the difficult
> AP's with the same dongle when its normal omnidirectional antenna is
> attached instead of the strong directional one. Could a failing
> antenna exhibit this behavior?
I'm extremely sceptical of these cheap external aerials. If it were an
expensive one from a specialist supplier then I might have higher
expectations, but I'm pretty sure a customer of mine used one similar
to yours, and they used to use a book to balance it at an angle to try
& get reception. This was between offices on adjacent floors, almost
one right above the other (surely less than 20' sideways).
If this is important to you, look at building your own directional
aerial - there are plans on various "guerilla wifi" sites, and it
seems like it's not hard to build an aerial which will get you very
good results indeed.
Stroller.
Grant Edwards
>
> On 8 Jan 2010, at 15:49, Grant wrote:
>> ...
>> That's a good idea, but I'm actually able to pick up the difficult
>> AP's with the same dongle when its normal omnidirectional antenna is
>> attached instead of the strong directional one. Could a failing
>> antenna exhibit this behavior?
>
> I'm extremely sceptical of these cheap external aerials.
The one to which the OP provided a link isn't that cheap ($50)
and gets universally excellent reviews. My testing indicates
that it does indeed provide something on the order of the
claimed 15dBi gain. It's performance is very close to that of a
well-built double-biquad reflector: both show 10-12dB increases
over a stock 3dB "whip" when I tested them with various bits of
HW (a USB WiFi dongle, two different brands of WAP).
That said, the cable on the Hawking unit is pretty flimsy --
and hence probably is rather vulnerable to both electrical
noise or physical abuse. It probably wouldn't take much of a
pinch or kink to cause problems.
--
Grant Edwards grante Yow! Here I am in 53
at B.C. and all I want is a
visi.com dill pickle!!
Grant
>>> AP's with the same dongle when its normal omnidirectional antenna is
>>> attached instead of the strong directional one. Could a failing
>>> antenna exhibit this behavior?
>>
>> I'm extremely sceptical of these cheap external aerials.
>
> The one to which the OP provided a link isn't that cheap ($50)
> and gets universally excellent reviews. My testing indicates
> that it does indeed provide something on the order of the
> claimed 15dBi gain. It's performance is very close to that of a
> well-built double-biquad reflector: both show 10-12dB increases
> over a stock 3dB "whip" when I tested them with various bits of
> HW (a USB WiFi dongle, two different brands of WAP).
>
> That said, the cable on the Hawking unit is pretty flimsy --
> and hence probably is rather vulnerable to both electrical
> noise or physical abuse. It probably wouldn't take much of a
> pinch or kink to cause problems.
That could definitely be the case. This thing has traveled.
- Grant
Robert Bridge
A lot of laptops now have wireless antennas in the display, so the
internal wifi may be using better antennae than you expect.
Grant
Can you recommend a specialist supplier, especially in the US?
- Grant
Stroller
On 8 Jan 2010, at 21:09, Grant wrote:
>> ...
>> I'm extremely sceptical of these cheap external aerials. If it were
>> an
>> expensive one from a specialist supplier then I might have higher
>> expectations, but I'm pretty sure a customer of mine used one
>> similar to
>> yours, and they used to use a book to balance it at an angle to try
>> & get
>> reception. This was between offices on adjacent floors, almost one
>> right
>> above the other (surely less than 20' sideways).
> Can you recommend a specialist supplier, especially in the US?
I had to google for recommendations to pass on to you, but found:
I've had great results mesh networking with 15dbi omnis
available from http://www.wlanparts.com. With line of
sight I can connect to these from over 1/2 mile a way with
my laptop. Watch your transmit power as with high gain
antennas its easy to venture in to illegal power levels.
See: http://www.rflinx.com/help/calculations/ Remember high
transmit powers only increase range if both ends increase
their power. In most cases increasing power does little
good at just one end of the link.
<https://forum.openwrt.org/viewtopic.php?pid=35766#p35766>
Indeed wlanparts.com would appear to be the kind of folks I had in
mind (they look to me like the kind of people you could email for
advice - if you were to email them the question you originally posted
to this list, maybe they could suggest a replacement?) but it might
also be worth searching openwrt.org & it's forum for aerial or antenna
and take a look at few more of the results there (i.e google "aerial
or antenna site:openwrt.org" will include the forums).
Stroller.
Grant
Thanks a lot, plenty of info there.
- Grant