[driverloader] enable/disable antenna?

[Jeramy Ashlock]

Hi, I have a Dell Truemobile 1400 on an Inspiron 5150 running RedHat 
9.0.  In W!indows, there is an option to turn the antenna off so that it 
is not consuming power and emitting radiation.  I tried the following to 
do this in linux:


# iwconfig eth1 txpower off
Error for wireless request "Set Tx Power" (8B26) :
     SET failed on device eth1 ; Operation not supported.


How can I be sure that the antenna is turned off when the interface is 
not activated (i.e. when I type /sbin/ifdown eth1)?

thanks