Nintendo Donkey Kong Jr Hum sound (need schematics)

[Sunshine (Elio)]

Hi.

As you know, most of these Nintendo arcade games seem to have 'speaker hum',
usually low pitched. Even by recapping the little sound amplifier board on
the Nintendo monitor, I still get the hum coming from my machine.

I think that this may be due to the PCB itself (and I have tried different
PCB which do indeed have different bad hum sounds, hence the PCB!!).

It may be the CAPs (electrolitic) on the PCB and I want to try if this is
indeed the problem.

I need the Schematics to the Donkey Kong Junior CPU PCB? Could anybody help
by provide a scan of the area before the Amp out (bottom right corner of
schematic)? The pages of my copy stuck together and the ink is faded now.

This might put an end to these Nintendo Hum problems that everybody has had
and still has....

Thanks.