[Coco] powering a coco2 3134 with DC

[didier derny]

I'm trying to power a coco2 3134 with DC

 

On the schematics the transformer entry is followed by a bridge

So I connected + 12  / -12 directly  on the transformer pins

 

The power supply is running  (producing +12 / -12) 

I have 4.98v on the VCC pins of the chips

 

 

But black screen

 

Any idea ?

 

Thanks

 

--

Didier