[Coco] The CoCo to VGA adapter

Charlie chazbeenhad at hotmail.com
Sun Jul 27 09:51:12 EDT 2008


<RJRTTY at aol.com> wrote in message 
news:d1d.2d1e9570.35bcfab1 at aol.com...
>
>
> There is one minor detail you should know about the converter.
> Well it is really about the coco3.   The coco3 generates  the
> three primary colors slightly out of sync with each other and
> the pixel clock.   Green is in sync with the pixel clock  but
> red is slightly out of sync and blue is WAY out of sync.
>
> What all of this means is that text looks good with
> black on a pure green backround.   Text looks ok with a  black
> on a pure red backround but text looks terrible with a black
> on pure blue backround.   The reason this doesn't show up
> with say a CM8 monitor is that the bandwidth is so much
> smaller with the old monitors that they "soak up" this
> distortion but the bandwidth of my converter on an SVGA
> monitor is greater and shows the original signal warts and all.
>
> The converter uses special input filters to correct this to some
> extent but it cannot eliminate it completely.   The bottom line  is
> to  avoid pure blue and pure red in text screens.
>
> Oddly enough blue with just a little green or red looks perfectly
> okay.  Same for red with a little green or blue mixed in and all
> other color combinations look okay too.   Go figure.......
>
> Roy
>

Hi Roy. Would WIDTH80 CLS3 show the text to be terrible as you say?
I just tried it out with your XRGB adapter and it actually looks fantastic 
on my NEC XV15.

Now that I have several LCD flat panels in my home with VGA inputs, I'll be 
ordering your VGA
adapter when I can get some extra cash together. It will be nice to play 
coco games on a big screen TV.
Everyone gives excellent reviews to your VGA box and it looks so easy to use 
vs this XRGB which is a mess of wires.
Plus after you told me yours busted im afraid to move mine :)

Charlie






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