Capturing Apple 2 composite signals

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Capturing Apple 2 composite signals

Hi all,

 

I'd like to complete my OSSC (VGA/Component/RGB capture card with HDMI output) with a composite input which works with Apple 2 machines. I know Apple 2 composite is a bit weird so I was wondering if anybody had any experience with any capture devices. I have a cheapo composite to HDMI which works-ish as in the signal is unstable with the Apple //e. 

 

For the OSSC there are a few options but basically anything which converts composite into component/RGB would work. The retrotinker is one option, the Koryuu (and clones) is another. But before ordering stuff I was wondering if someone had any experience with any of those?

 

https://videogameperfection.com/products/koryuu-transcoder/

 

Thanks!

Tony

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CVBS

The main thing non-standard with an Apple IIe is the video timing. The levels should be pretty much standard.

Going from Composite (CVBS) to Component video is not changing the timing, but just separating the chroma signals from the Video and Sync. So whatever solution you use is most likely not affected by the Apple's peculiarities, although the resulting component video will still be nonstandard in the same ways.

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Thanks. That's good as I feel

Thanks. That's good as I feel the OSSC is more capable of interpreting that signal. The issue I am seeing with my previous, cheap setup, is that the screen seems to change from B/W to Colour all the time. I see the text is alternating between being very clear and with colour artefacts all the time. Yes, I did tweak those trimmers, even using a scope, and I can sometimes make it better until I guess the Apple warms up and the signal is again slightly changed! :) 

I did see the same behaviour on my old LCD TV which had a composite input. 

 

I don't mean to advertise my own video (!) but you can see what I mea here: https://youtu.be/Eyc6LraD9O0?t=2110

 

For some reasons, I don't think I see that problem with the Apple //c. But The Apple //e works perfeclty fine in B/W with the monochrome CRT.

 

I know there is a small adjustment which should have something to do with the colour burst and I believe it was discussed here before and I ended up setting it up so to maximise some waveform I can't remember right now. 

 

 

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Hi all, I am still searching

Hi all,

 

I am still searching for a device to capture composite signal. On another forum I was recommended an Extron DVS 304 but either it's faulty or it doesn't like any of the signals I'm feeding it. I tried three different C64s, a ZX Spectrum and the Apple //e. They all showed the same issue so I suspect the Extron has an issue.

 

Before that I bought an "OSSC add-on" board from Aliexpress which worked a little then it stopped working and got 50% refund as apparently I have to pay for the "paperweight" feature.

 

Retrotink are telling me what you told me, Roberspierre, the signal output by the Retrotink would be non-standard and up to the HDMI capture device to deal with. 

 

 

I'm at a loss. I've tried 5 different devices over time.

 

Any Help is welcome!

 

 

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Are you dead set on composite

Are you dead set on composite? The new VGA card options are pretty solid and affordable now. 

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Most of the vintage 8 bit

Most of the vintage 8 bit micros play fast and loose with the NTSC spec.  The Apple II family in particular is just barely close enough to fool a monitor.  Most monitors anyway.  Back in the day people who wanted to record or broadcast the ouput from an Apple II usually had a challenge.  Some "broadcast standardizer" devices would do a pretty good job of cleaning it up.  Those devices were expensive and usually only big TV stations and studios had them, not your typical school AV department or whatever.  Some people had some success with running the composite out from an Apple II into a VCR (usually a Sony worked best) and then the output from that into something else.  Often the results weren't still weren't that great.  Colors were often funky, text hard to read and everything kind of fuzzy.  Trying to record on a home grade VHS unit often didn't work well at all, especially in anything but the lowest capacity mode.

 

Apple made a board for outputing better quality NTSC, the Apple II Video Overlay Board, but those are pretty rare and usually sell for a lot of $$$.  http://www.applelogic.org/files/AppleIIVideoOverlayCard.pdf

 

I have had some success using NTSC->HDMI converters with Apple IIs.  It seems to work better from a //e or IIgs than a ][+, especially in 80 columns.  But they aren't really great.  Might work better than trying to work with the composite video though.

 

I agree with skate that the Apple II VGA combined with a VGA->HDMI converter is a great way to go these days.  I've built 4 of the Vince Briel version now, and I'm looking to make a few of the Ralle Palveev version for use with ][+ and clones since they are supposed to be ablet to emulate an 80 column card as well.

 

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thanks for your input.I'm

thanks for your input.

I'm looking for something that works with the Apple but also with those weird video signals such as C64, ZX Spectrum etc. I have an RGBTOHDMI so I could wire it in the Apple //e and get pixel perfect picture but I'm looking for something that gives me a "good-ish" picture out of the composite socket. I have 5 different devices and - for a reason or another - they just don't work with anything! :) 

 

I'm reading that even the Retrotink has some issues now.  You can see the pain in this video of mine: https://youtu.be/l-cLiZzBxhw :)

 

I thought that given the bigger Retro community there would be something more recommended these days. 

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Even my trusty XRGB2+, which

Even my trusty XRGB2+, which by design handles crazy off spec arcade signals, struggles with Apple II composite in some video modes. I would recommend it for any other composite or s-video source any day, but they aren't cheap.

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if the Apple // is difficult,

if the Apple // is difficult, but anything else works, I can consider that but as you say it's not cheap. Right now I don't have anything that works reliably. 

I'm still puzzled that my DELL monitor seems to be happy-ish with the Apple (it might misbehave at times but mostly ok) but for the life of me I cannot find a good converter that does a similar job. That said, that 27" DELL I believe used to be the top of the line, I think it sold for £1000 back in the days (2007/2008) and comes with composite, component, SVideo, HDMI, Displayport. 

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What’s working for me atm

I'm pretty happy with these solutions for my Apple IIe at the moment - I have a dual monitor setup going from my Apple IIe Enhanced: Composite video to the monitor I purchased from Henry at ReactiveMicro.com ($155) which works extremely well I think (vibrant color and clear text in 40 and 80 columns / color text is still a bit strange but tolerable and my second monitor is an old 17" VGA CRT connected to Plamen's VGA scaler card from a2heaven.com ($85). Colors from the VGA scaler are interpreted differently it seems than composite but I love that you can change to green or amber and various modes with it so that I can have one color monitor and one monochrome at the same time. Not a cheap setup but works great for me. I realize these may not be the solutions you are looking for but thought I'd throw them out there. Btw there are some nice reviews of the 12 inch LCD from ReactiveMicro on YouTube by Chris Torrence and Joes Computer Museum.

 

m0ebiu5

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ahem no, I'm looking for

ahem no, I'm looking for something to digitally capture the signal into a computer :) 

 

My DELL monitor used to be a top of the line one and has all analogue inputs. It works brilliantly with Apple Signals but shooting a monitor with a camera is never fun - you need an extra camera which then is in the way. Then you have reflections. 

 

Meanwhile I have purchased a StarTech composite to HDMI converter and surprisingly it seems to be working well - not perfectly but ok - with my //e, my //c and also the Europlus and its weird NTSC signal. So I might have found the holy grail :)

 

 

 

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tony359 wrote:Meanwhile I
tony359 wrote:

Meanwhile I have purchased a StarTech composite to HDMI converter and surprisingly it seems to be working well - not perfectly but ok - with my //e, my //c and also the Europlus and its weird NTSC signal. So I might have found the holy grail :)

Your last picture was from your PAL Apple //e or Apple //c, wasn't it?

Although PAL can be inconvenient with the Europlus, it offers a special benefit with the European Apple //e and Apple //c.

In the picture of color bars, notice how white the text is in your picture.  That's typical behaviour of Apple graphics modes on a PAL receiver -- the text window is clearer because the Apple doesn't transmit a color burst on text lines, so a PAL receiver displays those lines in monochrome.

Here's how that screen appears on an NTSC color receiver.  Notice that the text is unintentionally colored.

In NTSC, the text is colored because the recever isn't affected by the absence of a color burst in that portion of the signal.  But PAL color requires a phase reference before every line of color video, so a receiver can't display color for lines that omit the color burst.  Thus the European models of the //e and //c get the accidental benefit of monochrome text, even in graphics modes.

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ohhh interesting! That's my

ohhh interesting! That's my PAL //e.

 

I wasn't aware that the Apple had the ability of removing the colour burst from specific lines? My understanding is that the //e is still adding the NTSC burst but then there is a trap to remove it and a PAL one is added. Are you saying that the circuitry to add PAL burst is smart enough to only add the burst when required? How does that happen?

 

I checked on my //c NTSC machine and you're right, text is fringed with green as in your capture! Amazing!

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S.Elliott wrote:...In NTSC,
S.Elliott wrote:
...
In NTSC, the text is colored because the recever isn't affected by the absence of a color burst in that portion of the signal.  But PAL color requires a phase reference before every line of color video, so a receiver can't display color for lines that omit the color burst.  Thus the European models of the //e and //c get the accidental benefit of monochrome text, even in graphics modes.

 

Actually that is not true. The colorburst is still there even for the 4 text lines at the bottom. The reason they look white is because PAL is much better at not artifacting than his older brother NTSC. Here is looking at one of the text lines on the bottom with an oscilloscope on my PAL Apple IIe:

 

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even more interesting! What

even more interesting! What software is displaying that nice colour bars pattern?

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Its using Apex II: download

It's using Apex II: download!

 

Since the video tests are written in Basic, I extracted them and also posted them here:

https://www.applefritter.com/comment/99404#comment-99404

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Apple //e schematic details of GR, CLRGATE, and FRCTXT
CVT wrote:
Actually that is not true. The colorburst is still there even for the 4 text lines at the bottom.

 

Sure enough!  I had erroneously traced the color-gate back to the wrong pin of the IOU.

 

Here's the relevant part of the schematic, with color-coded highlights to distinguish CLRGATE vs GR.

  • CLRGATE (orange) emerges from IOU pin 37 to enable the color-burst when graphics mode is enabled.
  • GR (green) emerges from IOU pin 2 to switch the 2732 ROM between text-pixels vs graphics-pixels.  It's completely independent of CLRGATE.
  • 3.58M (yellow) comes from pin 10 of the timing flip-flops at C1.
  • FRCTXT (blue) blocks the GR signal from reaching the master-timing PAL/HAL at D1 to allow double-resolution graphics by forcing the pixel clock to run at text-mode speed.  That causes graphics modes to interleave twice as many pixels in the same way 80-column text mode interleaves twice as many characters.
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