[mythtv-users] OT - MX4000 to FX5200

[Brian Wood]

On May 4, 2006, at 10:07 AM, Brad Fuller wrote:

> Kevin Kuphal wrote:
>> Brad Fuller wrote:
>>
>>> Brian Wood wrote:
>>>
>>>
>>>> On May 4, 2006, at 8:46 AM, Kevin Kuphal wrote:
>>>>
>>>>
>>>>
>>>>
>>>>> Brad Fuller wrote:
>>>>>
>>>>>
>>>>>
>>>>>> I'm going to swap out the cable. The first thing I thought of  
>>>>>> when
>>>>>> the
>>>>>> B&W popped up was that since the MX4000 works and the FX5200  
>>>>>> doesn't,
>>>>>> maybe the S-Video out voltage level is flaky and maybe at the  
>>>>>> edge.
>>>>>> Since I'm running a long cable (10ft of S-Video going to a
>>>>>> S-Video<->Composite converter and about 20ft of RG6) that  
>>>>>> maybe it's
>>>>>> just not making it somehow. I realize that this is no where  
>>>>>> near the
>>>>>> length limit, but what the heck.
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>> If you're plugging the S-VIDEO output into a Composite input you
>>>>> need to
>>>>> change the TV-OUT format line in your xorg.conf from "S-VIDEO" to
>>>>> "COMPOSITE".  That controls the color signalling that the card  
>>>>> sends,
>>>>> not the type of connector that it uses.  Having this set wrong  
>>>>> will
>>>>> result in B&W picture.
>>>>>
>>>>>
>>>>>
>>>> Depends on what type of "converter" he is using, but I agree  
>>>> this is
>>>> the root of the problem.
>>>>
>>>> Be aware that the adapter supplied with nVidia cards is *not* a
>>>> converter, it is simply ti allow you to access the composite signal
>>>> from the S-Video-type connector.
>>>>
>>>> But like I said, if his target is a composite input, there is no
>>>> reason to fool with S-Video at all.
>>>>
>>>>
>>>>
>>> The only difference between composite and S-Video is that  
>>> luminance and
>>> chroma are separated on S-Video.
>>> Unless the driver can tell the video board to combine Y and C and  
>>> send
>>> it out on a single pin (and indicate what pin it's sending the  
>>> combined
>>> signal on) then signifying "SVIDEO" or "COMPOSITE" in xorg.conf  
>>> works
>>> equally. I doubt that there is any difference between using  
>>> "SVIDEO" or
>>> "COMPOSITE" on a board that has only SVIDEO out.
>>>
>>> Do you have a different explanation?
>>>
>>>
>> I don't have an explanation other than that it works.  I have more  
>> than
>> one nvidia board with only S-VIDEO out where if I do not set the  
>> tv-out
>> format to COMPOSITE, I get a B&W signal when using an s-video to
>> composite cable connected to it.
>>
> I just tested it and it doesn't matter. And, obviously, with the  
> MX4000
> it worked fine.
>
> But, if I switch out the cable, I get color.
> So, the cable is the B&W problem.
>
> However, I still can't get xorg to recognize there is a TV at the  
> end of
> the long cable (no matter if it's set to SVIDEO or COMPOSITE).
> If I replace the long cable with a shorter one, xorg recognizes  
> there is
> a TV out there (actually, it's probably the nvidia driver doing the
> telling) and I get the second screen. With the longer cable, no go.

I don't know how it is detecting a monitor but if it some sort of DC  
continuity test then there would be some DC resistance value that it  
would decide was not a monitor, so it makes sense there would be  
length limit, although I would have expected it to be hundreds of  
feet, as sending composite video that far is not uncommon.

Perhaps using better quality cable, RG-6 is designed for RF usage.  
You might do better with Belden 88281 or something like that which is  
designed for baseband video.

>
> AFAIU, specifying ConnectedMontior "TV" suppose to force video out the
> SVIDEO port. I don't know why this doesn't work.

I don't know either but that switch to force things never worked for  
me either with a couple of different cards.