[Coco] Video adapters

[Chris Hawks]

---Reply to mail from RJRTTY at aol.com about [Coco] Video adapters

> In a message dated 4/26/06 10:56:47 P.M. Eastern  Daylight Time, 
> chawks at dls.net writes:
>>    Since they both  connect to the Coco3's RGB output, probably not.
>>But, If someone wants to  build an RGB 'Y' cable, we can try it.
>>Right, Roy?
> 
>>---End  reply
> 
>>Christopher R. Hawks
>>HAWKSoft
> 
> You can do that BUT  the input resistance of my converter is 50 ohms.
> If Christopher's device also  has a low DC resistance (50-75 ohms) then
> one or the other must increase it's  resistance to avoid overloading the
> outputs in order to use them  simultaneously..
> By the way Chris, if your converter  doesn't have a 50-75 ohm
> input resistance on the RGB signal lines (not on the  sync lines)
> then try applying this amount of parallel input resistance and  see
> if the image improves.   The output circuits where designed to drive
> this type of load.

    The input resistance of the color lines on the RGB to S-Video adapter
is actually 150 ohm (easier for the voltage divider to drop the signal
down to the AD724 spec). So a 'Y' cable might work.

---End reply

Christopher R. Hawks
HAWKSoft
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The only "intuitive" interface is the nipple.  After that, it's all learned.
    -- Bruce Ediger, bediger at teal.csn.org, on X interfaces