Output power Alfa AWUS 036H

[ToonVA]

Hello everybody,


I did some new experiments with my Alfa and i found on google you can adjust the output power from the Wifi Signal.

So i went looking for the command and i found some things

"iw reg set BO" --> Reply: nl80211 not found
"iwconfig wlan0 txpower 30" --> Reply: Error for wireless request "Set Tx Power" (8B26)

Does somebody know what this mean and how i get my output power closer to 30dbm

Because now it works on 6dbm.

Backtrack v 4.2
Apple Macbook Pro 15" medio 2010
Intel Core I5 - 2.4ghz 8GB DDR3 RAM
OSX 10.6.6
VmWare fusion

[TheFlyingDutchMan]

I have the same alfa and always start with 0 power. Then after reboot 20 power, but here is your fix:

You must first disable your alfa, set to 30 and then enable like this:

Unplug your alfa, close backtrack. When system shut down plug your alfa back in and restart backtrack
first do a "iwconfig"to see if your alfa is on wlan0
if it is enter this in the terminal:

airmon-ng stop wlan0
ifconfig wlan0 down
iw reg set BO
ifconfig wlan0 up
airmon-ng start wlan0

then monitormode is enabled on mon0

then: iwconfig
to see you actually set power to 30

to test injection: aireplay-ng -9 mon0

and do your work with mon0 instead of wlan0

gedag.

[ToonVA]

I tried but it doesn't work

after i do what you said, the output is "off"


Is this because i am in Vmware?

[TheFlyingDutchMan]

Did you switch your card on with the vmware button?
Or you could try with sudo.

[sttlnb53]

I have backtrack installed on my HD and I also boot it up in VirtualBox with Windows 7. This works for me if I want to set the txpower to 30 in either case.

airmon-ng stop wlan0
ifconfig wlan0 down
iw reg set BO
ifconfig wlan0 up
airmon-ng start wlan0

I do this as Flyingdutchman said but if I type iwconfig in right after this my txpower is still at 20. So I use one extra command.

iwconfig wlan0 txpower auto

^This sets my txpower at 30.

[comaX]

... So I use one extra command.

iwconfig wlan0 txpower auto

^This sets my txpower at 30.

More generally speaking,
# iwconfig wlanX txpower 30
# iwconfig wlanX txpower 1000mW
would set txpower to 30Dbi, whatever the card, as long as it supports it.

[sttlnb53]

More generally speaking,
# iwconfig wlanX txpower 30
# iwconfig wlanX txpower 1000mW
would set txpower to 30Dbi, whatever the card, as long as it supports it.

For some reason if I try to set my tx power and specify specific numbers like this with the rtl8187 driver I cannot I get an error. Only with the r8187 driver am I able to use a more specific description. With the r8187 driver though I have terrible reception of signals so I don't use it. This is probably a user error but that is what worked for me.

[comaX]

For some reason if I try to set my tx power and specify specific numbers like this with the rtl8187 driver I cannot I get an error. Only with the r8187 driver am I able to use a more specific description. With the r8187 driver though I have terrible reception of signals so I don't use it. This is probably a user error but that is what worked for me.

I have exactly the same card, so you should be able to do it just as I do. Make sure your card is down (ifconfig wlanX down) before trying to change regional settings. Then you can try
# iw reg set BO
# iwconfig set txpower 30
(#iwconfig [for checking])

In case you'd have started networking before that (networking start or wicd start), try to do those manipulations even before starting Xserver.

keep us posted

[dismas]

Hello everybody,
"iwconfig wlan0 txpower 30" --> Reply: Error for wireless request "Set Tx Power" (8B26)

iwpriv wlan0 highpower 1
then your
iwconfig wlan0 txpower 30

[ToonVA]

I still can't get the output power to max (30)

I think i is because of Vmware.

I will make a movie from the commands i use so you can see what is happening