Transmit Power

Hello everyone! I have just discovered that after saving our Airport's configuration file to our computer and opening it via a Text Editor would then reveal the Transmit Power settings for both the 2.4GHz band and the 5GHz band. It's key name is "raPo", which could be easily decoded as, Radio Power. My defaults are set at 100. When i changed the value to about 200mW, the Airport Utility (6.3.2) would not allow me to update the changes, and would state that the "Transmit Power settings are too high". On Airport Utility 5+, it would update at first initially, then return back with a transmit power setting of 10% in the Wireless Option page.

1) Are the values under the key "raPo" (Radio Power) percentage based? or is it just number based?

2) If the value is number based, then how do i bypass the error when trying to update the settings to reflect the new Transmit Power?

I think this is worth discussing, as going through a wall (in my house) would bring the signal down by 2 lines on my various AC devices (ZENFONE 2, LG G4), and that my link speed would drop from 433Mbps to 292Mbps even when i am downloading files in the background. (there's actually quite a lot of difference in the speed that i am achieving with either the 433Mbps link rate or the 292Mbps link rate)

Thank You!