[Coco] cga to vga converter

[Retro Canada]

but a single 74sl04 will do the job

Sent from my iPhone

On 2013-03-03, at 4:15 PM, camillus Blockx <camillus.b.58 at gmail.com> wrote:

> 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
>> 
>> --
>> Coco mailing list
>> Coco at maltedmedia.com
>> http://five.pairlist.net/mailman/listinfo/coco
> <th_SyncGreen.png>
> 
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco