Got a DK jr board last weekend. It powered up and played but the background
was missing and many sprites were corrupted. The picture was also shifted
to far to the top of the screen, I couldn't see the high score or DK's head.
Pulled the board and the horizontal pot on the video board was busted.
Tried fixing it, but no joy. The pot's resistance is 30K - 50K, so I
removed it and soldered in a 42K 1/2 watt resistor into the holes left by
the outside legs. Worked great, the picture is right in the middle. And
there is still a horizontal adjustment on the monitor to fine tune it.
FWIW, if the horizontal pot's connection is open, the screen image is too
high. If you jumper the connection with a wire (zero K resistor), the image
is too low.
The background and sprite issue was fixed by replacing the EPROM's found at
3N and 3P on the video board. They both had multiple broken legs on them.
Now I just need to figure out how to leave both boards mounted in the cab,
but switch back and forth. And no, I don't want to DDK the jr. board. It
messes up the sound in DK.
Sean McLachlan
MIS Manager
LithoFlexo grafics inc.
801.484.8503
