Clock on RB4 Navigation

Does anyone know how to keep the clock on the RB4 to stay on?  For example:  instead of having a blank screen when the unit is turned off, to have the clock displayed when it is turned off.   Would be kinda nice to have the clock shown on the screen instead of a blank screen when the unit is turned off.
 
Thanks

if u have an owners manual it should say in there. if not u will haft to describe to me which rb4 u have and i will see what i can do there are severay rb4 with different settings.

I looked thru the book but couldnt find any reference to it.   I can hit the time button and it shows the time briefly then turns off.   I just would like it to remain on when the radio is off.
 
Im not sure what info you need, but when i go in and look at the version info for the RB4, it says headunit : 2070  and navcd :   .2  AA
 
Does that help?
 
Thanks,
                                               

What version dvd do you have for the nav the part number is right on the disc