[Coco] 6847 Video (newbie question)

[Brett Gordon]

I'm not an EE, but aren't CbOut and CrOut just emitter-followers?  I
don't think they need ground. The current sink is the "grounding".  I
Wonder why the "Y" has two transistors stuck on it.   One voltage
inverter amp followed up by anther emitter follower (current amp).   Y
must be inverted?

B

On Sat, Nov 1, 2014 at 9:48 AM, Retro Canada <retrocanada76 at gmail.com> wrote:
> don't know about the pulldowns, i got the scheme from Daniel.
>
> the image is pristine.
>
> On Nov 1, 2014, at 6:19 AM, Tormod Volden <lists.tormod at gmail.com> wrote:
>
> On Fri, Oct 31, 2014 at 10:03 PM, Luis Antoniosi (CoCoDemus)
> <retrocanada76 at gmail.com> wrote:
>> It works, but you need to make a driver:
>>
>> https://pbs.twimg.com/media/BCb7-hoCEAAJm22.jpg:large
>
> Shouldn't the CbOut and CrOut drivers have a resistor from emitter to ground?
>
>>
>> When I used my it suffered from severe jumps time to time. maybe you have
>> better luck and a better board.
>
> Apart from the jumps, what does it look like? Perfectly sharp and
> stable picture with good colours?
>
> Regards,
> Tormod
>
>>
>>
>> Luis Felipe Antoniosi
>>
>>
>>
>>> On Fri, Oct 31, 2014 at 3:58 PM, didier derny <didier at aida.org> wrote:
>>>
>>> I just received a GBS 8220 and I was wondering if the YPBPR entries of the
>>> GBS 8220
>>>
>>> Were compatible with the Y phiA phiB of the 6847 ?
>>>
>>>
>>>
>>> Are they the same signal with another name or something different ?
>>>
>>>
>>>
>>> Not really understood fig 10 of the 6847 datasheet
>>>
>>>
>>>
>>> I often used composite or rgb but never  YPBPR or the signal of the 6847
>>>
>>>
>>>
>>> Any idea ?
>>>
>>>
>>>
>>> Thanks
>>>
>>>
>>>
>>>
>>>
>>> --
>>>
>>> Didier
>>>
>>>
>>>
>>>
>>>
>>>
>>> --
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> https://pairlist5.pair.net/mailman/listinfo/coco
>>
>> --
>> Coco mailing list
>> Coco at maltedmedia.com
>> https://pairlist5.pair.net/mailman/listinfo/coco
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco



-- 
Brett M. Gordon,
beretta42 at gmail.com