Not necessarily, If the SSID isnt being broadcast Netstumbler wont see
it,
other than that it would work great. I think they have a mini-stumbler
to work
on handhelds.
I've been looking at handheld wireless connection "sniffers" as a way
to locate open wireless connections and strengths. Anyone tried one of
these? I see them on EBay for as little as 8 bucks but know nothing
about them. I plan to set up a wireless network at our new building
and want to be able to see what I got and where.
TIA
JohnF
It's just a PITA stumbling around with my laptop trying to detect a
conection. A little hand held thingie would be great, just pull it out
of my pocket and see what is around. I know there are some dead spots
here at work but I don't want to drag the damned laptop around
especially when half the time I'll have to set it down in the crap in
the shop to fix somebodys machine. Those sniffers would be perfect and
for only about $8.00 you can't go wrong..............IF they're worth
a damned.
JohnF
seems to tickle more avail info & eye candy too.
I recall someone talking about a real low buck wifi detector, said it might
be good for finding leaks in your microwave door if you held it real close.
I have several microwave oven leakage detectors. The most sensitive
will respond to 1mw/cm^2. 5mw/cm^2 is considered a leaky microwave
oven. It will barely respond when place next to my access point
antenna. I also have some Proxim 7400 frequency hopping cards that
are setup with tweaked firmware to act like a spectrum analyzer.
They're not terribly sensitive (lack of processing gain and
synchronous detection), but do show the classic direct sequence
spectra and microwave oven leakage. I borrowed a Kensington WiFinder
and found that it would not detect 802.11g access points, was
basically comatose, and falsely responded to spread spectrum cordless
phones (Panasonic Gigarange).
Great idea. I just tried it with several cordless phones I have
around the house. All of them, including the 900Mhz flavor, responded
inside the microwave oven. I could probably calculate the attenuation
provided by the oven, but my guess(tm) based upon screen room
characteristics is that it's about 60dB. 60dB down from about 600
watts CW power is conveniently 600 milliwatts of leakage, which is not
enough to do any human damage, but is certainly more than what an
802.11 radio belches. For the cordless phone test, the average base
unit belches about +10dBm. 60dB below that is -50dBm. Path loss to
the handset drops perhaps another 40dB (at 6ft) for a -90dBm receive
signal. That should be sufficient for the cordless phone to respond.
Actually, if you look carefully, many 5.6Ghz cordless phones are
crossband type that use 2.4Ghz in one direction and 5.6GHz in the
other. It's much easier and cheaper to build a full duplex system
(diplexer) with radically different frequencies. I don't have a list
of which ones do this. Lookup the FCCID on your cordless phone and
dig through the test results.
Ugh. I had to look that one up and found this physics class notes:
|
formatting link
(Heating%20Water%20with%20Microwaves).pdfWater molecule resonates at about 22Ghz. Apparently, the selection of
2.45Ghz was quite arbitrary.
"bumtracks" wrote in message
That sounds like pure marketing. If anything, such a detector'(detecting
raw continuous wave RF) would be less desirable than a detector that
specifically detects 802.11 frame formating since it would be prone to false
readings.
Microwave's have a CF at 2.45 Ghz, which is attenuated well by the
microwave, but you'd be surprised how much 2.4 Ghz is escaping. At work, we
looked at a microwave operating in another room on a spec annie. You can
do the opposite at home by simply placing a 2.4 Ghz cordless phone handset
inside a microwave, shutting the door, and hitting the "page button" (or
calling from another phone) on the base unit. The handset will beep/ring
with no problem. Or simply look at the noise floor, using Netstumbler,
while relatively near a microwave. Microwaves play major havoc with
802.11g/b. (One of the main reasons I'm using 802.11a for my WLAN traffic,
as have many cordless phones and microwaves in the house.)
Off-topic but interesting tidbit on microwaves. Common misunderstanding on
how microwaves work is that the resonance frequency of water is at 2.4 Ghz.
Been a while since I've taken physics, but I do recall that the resonance
frequency of water is in the 20-something Ghz range. Water, a dipole
molecule, can vibrate by the E/H fields caused by a wide range of
frequencies. 2.45 Ghz was chosen for the kitchen nuker out of government
mandate (at least in the US) since its in the "junk band". 2.45 Ghz also
allows the cavity size of the magnetron to be managable for the
manufacturers. Finally, if the microwave used 20-something Ghz to cook food
it would scour the outside of that frozen burrito while leaving the inside
completetly frozen as higher frequencies attenuate much easier.
Cheers!
-Eric
Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.