wifi-radar is a nice utility used to manage wireless connection. Is easy to use but sometimes, if you use a WPA key, something can goes wrong! You can see error messages like this:
TypeError: not all arguments converted during string formatting
wpa_args = WPA_SUPPLICANT_ARGS % ( INTERFACE, profile['wpa_driver'] )
NameError: global name 'WPA_SUPPLICANT_ARGS' is not defined

This how-to can try to help you.

First of all, you need to have the wpa_supplicant package

#dpkg -l | grep wpasupplicant

if you see an empty line

#apt-get install wpasupplicant

Now we need to setup it:
# wpa_passphrase essid pass_wpa

where essid is the name of the wireless network we need to connect and pass_wpa is its WPA key

we see something like this
network={
ssid="essid"
#psk="pass_wpa"
psk=7d20d1e0391b4d59dc22314476a838b0f33aa488da776206a7d59ec30592c2da
}
Make a file called wpa_supplicant.conf in the folder /etc:
# nano /etc/wpa_supplicant.conf
ctrl_interface=/var/run/wpa_supplicant
fast_reauth=1
network={
scan_ssid=0
ssid="essid"
proto=WPA
key_mgmt=WPA-PSK
pairwise=CCMP TKIP
group=CCMP TKIP WEP104 WEP40
#psk="pass_wpa"
psk=7d20d1e0391b4d59dc22314476a838b0f33aa488da776206a7d59ec30592c2da <-(valore dato dal precedente comando)
}

Now edit the file /usr/sbin/wifi-radar and make this changes:

line 76 (about), be sure that dhclient is the first value like this
POSSIBLE_DHCP_CLIENTS = "dhclient dhcpcd dhclient3 pump"

line 143(near WPA_SUPPLICANT “area”), make the same changes
WPA_SUPPLICANT_CONF="/etc/wpa_supplicant.conf"
WPA_DRIVER="wext"
WPA_SUPPLICANT_ARGS = "-B -D"+WPA_DRIVER+" -i"+INTERFACE+" -c"+WPA_SUPPLICANT_CONF
where
wpa_supplicant.conf is the file we have made before
wext is the driver of your wireless card (wext is the common driver)

line 430
wpa_args = WPA_SUPPLICANT_ARGS % ( INTERFACE, profile['wpa_driver'] )
substitute it with
wpa_args = WPA_SUPPLICANT_ARGS

All changes are done. Save all, exit, restart wifi-radar and cross your fingers.

linux, wifi-radar, wireless, wpa, wpasupplicant