Bang and olufsen B&O Penta speaker amplifier 6602 circuit diagram

Hiya, am seeking a Penta amplifier circuit diagram. I have found a few on the web but this request relates to the input board. Early Penta Mark1s used an input board numbered 8002831 and used 6 transistors. my board is numbered 8002831E and looks similar  - but in addition to TR1 to TR6 I have TR8 Tr9 TR10 TR16 TR16 on the circuit board. As its this board that is not working i'm quite keen to get hold of the right circuit diagram. The case says Penta 6602. Any help greatly appreciated. Happy New Year