PLease help -

I have a base Pro-2006 400 channel scanner plugged in to the wall all
the time and I just bought a 9-v type battery for the backup
power...The battery fits into those prongs or whatever there called and
I closed the protective cover after I tucked in the battery
inside...Now as I unplug the unit from the wall, it does not turn
on....How come? What do I need to check if the batter placement is
correctly inserted or not?

Its suppose to turn on right?? Even with the outlet plug unplugged from
the wall....

Beats me...

And these are fresh batteries too...I just got them.