[Coco] powering a coco2 3134 with DC

[didier derny]

Hi

No AC is totally removed, in any case it was removed after the diode bridge
No connection between AC and the rest of this machine (for the 3134) 

Finally the machine is working,  check all the tensions they were correct

The problem is with Zippster composite board, it's not working since I connected DC

I removed the mc1372 on this board and connected by board, I have an image

I guess that now the white / red wire of his board are not receiving the right tension

I checked the mc1372 on his board, it receives GND+VCC 5v at the right place

I guess I need his advices 



My problem:  I was using a 230v to 110v transformer + coco 2 transformer outside of his box
             I prefer a safer power supply :)




-----Message d'origine-----
De : Coco [mailto:coco-bounces at maltedmedia.com] De la part de Steve Batson
Envoyé : mardi 21 avril 2015 22:48
À : CoCoList for Color Computer Enthusiasts
Objet : Re: [Coco] powering a coco2 3134 with DC

Is AC passed to any other part of the board? 

Steve Batson
Batson Photography
"Today's Special Moments, Tomorrow's Priceless Treasures"

Website: http://www.batsonphotography.com
Blog: http://www.batsonphotography.com/blog
Our Free Photography Site and Forum: http://www.digitalphotographerzone.com

> On Apr 21, 2015, at 1:34 PM, didier derny <didier at aida.org> wrote:
> 
> 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
> 
> 
> 
> 
> -- 
> Coco mailing list
> Coco at maltedmedia.com
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