>>> 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.
That could definitely be the case. This thing has traveled.