For some reason my ASUS Transformer has it’s Wi-Fi transmitter running at 1.6 watts (32dBm). This increases power consumption and so shortens battery time.
The standard for most netbooks is 14dBm. The ASUS Transformer allows for the following values: 4dBM, 11dBm, 18dBm and 32dBm. Fortunately, there is a way to lower the power used by the Wi-Fi transmitter.
YOU NEED TO BE ROOTED and have some kind of terminal emulator
Simply download this file: iwconfig.tar (registration required!) and do the following from the terminal emulator
cd /mnt/sdcard/download — this assumes the download location of the file
tar –xf iwconfig.tar
mount –o rw,remount /system
cp iwconfig /system/xbin
chmod 755 /system/xbin/iwconfig
You can see the current value by running the following command:
You should see that the current, default value is 32dBm for the wi-fi transmitter. You can change the value by typing the following (for example):
iwconfig wlan0 tx 11dBm
You can also set this up in cron to always lower the setting on boot. Again, in terminal emulator:
In the editor (vi for me) that opens add a line that says:
@reboot /system/xbin/iwconfig wlan0 tx 11dBm
Save the file and reboot. After successfully rebooting, check the current value by running iwconfig again. It should show the value you used in crontab (11dBm in my case)