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g33k
Using a command like

CODE
iwconfig eth0 txpower 15


or

CODE
iwconfig eth0 txpower 30mW


ought to allow one to adjust the power of one's wifi card.

With pdaXrom, I get

"SET failed on device eth0 : Operation not supported."

with both a Symbol LA-4137 and a D-Link DWL(something) in a C-860. In fairness, I've never used the Symbol with any other ROM... but the D-Link was used quite a bit in a 5500 with OpenZaurus and was perfectly happy to adjust it's power level.

The larger issue is that neither the Symbol or the (hellishly powerful) D-Link detect much of anything with Kismet under pdaXrom. Increasing the txpower traditionally solves this problem - or at least helps.
alibosworth
sorry, i dont have any ideas about why you are unable to set the txpower, when i get home i can try the command you specified on my ambicom.

but i fail to see how adjusting your transmit power would have any effect on kismet's sensitivity in detecting APs. kismet does passive detection, as far as i understand it, your card need not even send out any packets when your are running kismet in the detection process.

i suppose changing the txpower on a card that supports it could also change the recieving sensitivity, but it would seem to me that this would all depend on the specifics of the card firmware/chipset.
g33k
I understand what you're saying; my reaction was exactly the same. My Linux guru work pal assures me that txpower does impact the "receiving strength" as well, though. In the past he wrote scripts to get Kismet working optimally which included maxing out the txpower and apparently this made the difference.

I was prepared to believe that the Symbol wifi card I'm using is just wimpy and that's the whole problem with my Kismet, but he showed me how his monsterous D-Link card is scarcely able to detect anything with Kismet, either. This makes me think that something is wrong, wifi-wise, with pdaXrom or with the Kismet build in the feed.
alibosworth
i havnt noticed anything strange.
i dont have a whole lot of experience to know, but i have found hundreds of APs with my c860 and ambicom card in my bag while biking. i was actually pretty surprised because i thaught it wouldnt pick up much.
i found 80 on my 10 ride home from work.
i found my results to be consistant with what i would expect from the area based on past laptop scans (although those were with netstumbler, so kismet should discover more because it sees those not broadcasting ssid)
anyways, i dont know.
jerrybme
QUOTE(g33k @ Jan 7 2005, 02:24 PM)
This makes me think that something is wrong, wifi-wise, with pdaXrom or with the Kismet build in the feed.

I've been wondering the same about the Kismet build in the feed. My card has problems in Kismet with channel hopping, occasionally it'll work for several minutes then stop. On the Cacko ROM, Kismet works fine as does Wellenreiter. I used to have a SMC card and it worked fine with Kismet on RC5, so I thought it was a kernel patch issue. Sashz & Laze patched the RC8 kernel, but it hasn't helped.

Meanwhile, I'd love to see someone compile Wellenreiter for pdaXrom, I like it better than Kismet.

Cheers,
Jerry
Laze
We are probally switching to the most more stable hostap drives - but you can do it yourself until the next update.

Just read the post by rgrep here http://www.oesf.org/forums/inde...indpost&p=44759

This greatly improves the stability of the wireless drivers - don't know if it allows you to set the txpower though - my zaurus is resting at home..
g33k
Thanks for the suggestion. I followed rgrep's directions, but my wifi card didn't seem to be supported by the hostap driver. The card was recognized and the modules modprobed, but I can't bring up eth0.
Laze
if the hostap drivers are running its named wlan0 - please try a ifconfig -a
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