[Coco] cga to vga converter

[camillus Blockx]

I always use two resisters to combine two different signals, i guess it
would work for video sync signals too.

In attachement you see a schematic on how to get -H +-V Sync on green
signal.
If signal does not ask to be inverted then take out the transistors. This
also goes for the green, leave it out an combine th H and V together with
two resistors of the same value. Start with a two variable pots of 10 K ohm
Linear and set it on the best working value by trying. Once you have a good
result youcan measure then pots value and replace them with resistors of a
fixed value.

Hope this helps

cba
SP picture included was taken from internet, with all credits going for
him/her who posted it.



On Sun, Mar 3, 2013 at 12:02 PM, Retro Canada <retrocanada76 at gmail.com>wrote:

> the ghost is not interference but the way the board works. any faster
> moving    object will produce it like typing characters too fast. i ditched
> my board in my storage box but seems related to the way it reconstruct the
> image internally.
>
> any nor gate will work i plugged the synced signal on pin 10 on the coco
> rgb output. but first you need to disconnect this pin by pulling on side of
> resistors 61 and 62 iirc.
>
> Sent from my iPhone
>
> On 2013-03-03, at 9:51 AM, Frank Swygert <farna at amc-mag.com> wrote:
>
> > Could someone post a simple sync combiner circuit that should work with
> the GBS 8200 board? A couple people are using them now, so someone should
> be able to test it. I'm wanting it mainly for an update to Tandy's Little
> Wonder, which I hope to work on soon. I'll be posting info on Roy's and
> Chris's converters, but will put the GBS-8200 info in as well.  As I posted
> earlier, a shielded case should alleviate the interference problems, and
> that might solve the ghosting on action games as well -- that could be
> interference related. If someone has a better idea, maybe some kind of
> signal filter, to at least reduce that problem I'd certainly like to hear
> that also.
> >
> > I'll have to rescan some images for TLW, and I may need some assistance
> there as I don't have most of the original images. They were pulled from
> various Internet sources and did not convert to PDF very well. For a good
> print edition I need higher resolution pics before the PDF conversion.
> >
> > --
> > Frank Swygert
> > Editor - American Motors Cars Magazine
> > www.amc-mag.com
> >
> >
> > --
> > Coco mailing list
> > Coco at maltedmedia.com
> > http://five.pairlist.net/mailman/listinfo/coco
>
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> Coco at maltedmedia.com
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>
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