[Coco] Coco-3 to the GBS-8220 upscaler interfacing

[Kandur]

Progress report.
Having read that, I just connected the H+V sync wires from the Coco, 
to a 10k pot's one side, the  GBS-8220 board's 'S' input to the middle,
and a 1k resistor to the other side, the other end of it was grounded.
Got a rock solid display. See the photos.

http://qdv.pw/eng/_photos/Computers/Coco/coco-3%20to%20GBS-8220_6034.jpg 
http://qdv.pw/eng/_photos/Computers/Coco/coco%20screen_6013-1024.jpg 

Like you said, the display is ok, but not as good as on an analogue crt monitor,
Can we have anyting better for $27 and free shipping?
Would you mind to share the web site's url,  you quoted?

Kandur

Thursday, June 5, 2014, 5:16:30 AM, you wrote:
> On Wed, 4 Jun 2014, Kandur wrote:

>> Thanks.
>> This circuit seem to assume negative sync inputs,
>> while the Coco-3 has positive sync outputs.

> From the web site:
> <quote>
> The sync signal combiner has a system to adjust to different sync
> polarities so that it always makes correct
> composite sync signals. VGA 
> card uses different sync signal polarities to tell the monitor which
> resolution is used. This circuit adjusts to
> sync signal polarity changes 
> in less than 200 milliseconds, which is faster than setting time of a
> normal VGA monitor in the display mode change.
> </quote>
> It's actually a very clever design.
> --