[Kenwood] TS-870 Power Output Menu "A7"

[hamradio at twcny.rr.com]

Folks: I am trying to adjust the power output of my 870 while in the A7 menu.
When I enter the A7 menu it says 100 watts on the far right,
when I turn the M.CH/VFO/CH this does not change but the 2 digit number on the left changes.
I do see that this does increase the power but it continues to say 100Watts on the right of the display. 
Does anyone know what I should adjust this value to be?
Right now my A7 reads as follows

A7        A6       A6     PWR100W


Also, does the value to the right ever change from 100Watts

thank-you 
Nick
N2HSM