Problem with getting 12V from AVR Doper

Hi,

Just as I mentioned in the subject, I have a problem with getting 12V on D3 cathode (I have ~4,75 instead). I used BC547B instead BC548, and BC557C instead of BC558. They have similiar characteristics, but since I'm not sure how exactly this circuit works it may be wrong replacement. I'll appreciate any help.

Strej.