Tapping into the motherboard to get better video in a PAL IIe

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Tapping into the motherboard to get better video in a PAL IIe

Hey Folks,

I've been doing some looking around to see if I can find an answer to this question: Is there somewhere upstream of the Composite socket you can tap into to get a "better" video signal, and by that I mean a signal in a less combined format.

(I suspect the answer is "no", but I'm just not that good at following schematics)

I ask this quesion because many of the retro-computers I own have a way of getting to either RGB or Chroma / Luma by simply going a little way "upstream" before the video gets combined into Composite. When you CAN get at these upstream sources, you can usually "tap in" to get a MUCH nicer video output. Some even have it on a connector, but that doesn't appear to be the case with the IIe :-)

If there was a point I could tap out Chroma / Luma, I could feed it out into an SVideo input on a monitor. (My Commodore 64 connects via SVideo and it's noticably crisper via Svideo)

 

I know there were once RGB cards, but I suspect they're as rare as hen's teeth now and priced to match. I'm not looking for a super professional solution, just a bit more crispness on the game I'm playing (*cough*Ultima V*cough*). I'd much rather build something myself rather than buying something "off the shelf" in any case.

 

Cheers, and thanks in advance for any advice!

Chesh

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I have several //e RGB cards.

I have several //e RGB cards. I've been on a side-mission to document differences. 

 

The video signal is TTL digital RGB, and if you want more details, an can make something useful, we can discuss loaning one, but they aren't that rare. AE, Checkmte, and Apple, as well as others made them. Right now, I use an AE addon RGB gaughtercard for the AE RAM boards, with my Monitor 100.

 

There are probably perople on this forum who own these cards and don't know that they offer this feature.

These only work on the NTSC //e. 

 

If you own a Digicard, it also has this capability. 

 

AROD is out of stock, but this is the base Apple card (p/n 699-0221):

http://www.applerescueofdenver.com/products-page/memory-apple-ii/apple-iie-extended-80-column-rgb-card/

 

If you want, I can photograph the same screens on my //e with the RGB display (Apple Colour 100), and my //c+ with the AppleColour Cmposite Monitor. The only major difference is DHRG. I can view things such as GEOS or A2D without needing to enable monochrome mode: The colour fringe artefacts in this mode are reduced, but this can be bad at times due to some software relying on them. It's not a straight upgrade, and in the mid-80s, I had both the RGB and a colour composite display simultaneously connected to the same system.

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Composite-to-HDMI connector

Have either of you tried the composite-to-HDMI connectors with a //e?

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PAL IIe

@Timelord: This is a PAL machine so it looks like RGB Cards won't help me out anyway. Mostly I was hoping to boost the existing signals, not generate a parrellel, possibly incompatible signal. I was hoping there was either CY or RGB being generated then combined to composite. (I can work with either of those). Also I'm in the wrong part of Australia. (The next capital is over 2000Km away). Apple gear doesn't come up often over here and shipping is a b*tch.

 

@Mutant_Pie: I did try a cheapo one and it was terrible! Rolling frames, blurry picture, inconsistent colour. My expensive one is unfortunately wired in to a cabinet full-o-gear, but I might try pulling it our this weekend. 

 

Thanks for everyone's replies.

 

Cheers!

Chesh

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I don't know if you could tap

The Apple II has no chroma signal to split from luma- it generates bit patterns that are interpreted by the monitor as a chroma signal as a "trick". 

However, even if if did have a real chroma signal, you would lose all color, because the artifact color requires the quirk in how the NTSC composite signal is interpreted by the monitor, and this won't happen if you were able to split the signals.

There is some information about this here:

https://www.kansasfest.org/wp-content/uploads/2009-ferdinand-video.pdf

 

The IIgs is also able to do RGB natively...

 

 

 

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rittwage wrote:The Apple II
rittwage wrote:

The Apple II has no chroma signal to split from luma- it generates bit patterns that are interpreted by the monitor as a chroma signal as a "trick". 

However, even if if did have a real chroma signal, you would lose all color, because the artifact color requires the quirk in how the NTSC composite signal is interpreted by the monitor, and this won't happen if you were able to sp

Except this is a PAL machine, and can't possibly rely on NTSC colour artifacting. Thus my confusion. 

How are PAL systems generating their colour? I assume there must be a different way if you can't rely on Woz's hack.

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I am using VGA extender for my Apple IIe.

I use regular LCD monitor connected via the RGB port to VGA extended card which supports both PAL and NTSC coded video signals. The RGB signal is generated by VGA extender card which gets its signals from Ramworks card.

 

This is the card:

https://a2heaven.com/webshop/index.php?rt=product/product&product_id=152

 

This is the manual:

https://www.a2heaven.com/webshop/resources/pdf_document/18/84/e.pdf

 

There is a standalone card which does not require Ramworks board to connect to, but there are some additional connections which need to be provisioned to tap some required signals ( https://a2heaven.com/webshop/index.php?rt=product/product&product_id=142 ).

 

The person who developed these cards can be reached at: info@a2heaven.com in case you want to shoot specific questions.

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VidHD by BlueShift

What ever happened to this...?

https://vintageisthenewold.com/announced-vidhd-4th-generation-video-card-for-the-apple-ii/

The manual for it is here:

https://www.callapple.org/vidhd/

 

The manual says it has both NTSC and PAL modes.

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it looks very interesting as

it looks very interesting as it doesn't try to convert the fake video signal into digital but it reads the video bus and generates the video from there. 

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Sorry, I missed that you had

Sorry, I missed that you had a PAL machine. I have never seen one here in the US, but some searching shows that the PAL IIe contains the circuitry of the Apple PAL color card on the motherboard. 

I did find the schematics for the original card here:

http://john.ccac.rwth-aachen.de:8000/patrick/data/PALcard.pdf

 

Good luck!

 

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If you find the VidHD...

If you find a source for these, let me know.  I couldn't locate one and the creators are not responding to my purchasing inquiry.

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That schematic is for the PAL

That schematic is for the PAL board for the ][+

 

If there were a market for them, I would make them, but I would be hard-pressed to sell a run of 100. 

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