Agila Radio de-activate radio code?

I have an Agila with radio cdr2005. How do I disable the anti-theft device. I have the code and can get the radio off 'safe' mode, but the radio has a dodgy on/off power button and it is getting increasingly difficult to use so I leave it on.
This would be fine, but also have a dodgy battery (dispute with AA) and am having to get it off safe mode rather too often.
There are instcuctions in the manual which make no sense to me!