Power supply circuit diagram

[Aley Keprt]

Hi guys, does anybody have the original Sam Coupe power supply unit circuit 
diagram?
My power supply was damaged years ago and somebody repaired it by replacing 
something inside with an old big zener diode. I just remember that 12V line was 
dead and that diode is just a random one which we were able to get. Then in 
90's it was not easy to buy good new diodes here, but it is easy to buy 
anything on internet now. So I just need to know what was the original piece in 
the PSU and I am going to replace it back.
Thanks in advance.
Aley Keprt