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Composite to VGA adaptor...any one use one?

I don't have such an adaptor, but I can tell you that the quality of composite output is an insult to a vga monitor. It's better to go from RGBI or other monitor output, if that is doable. If you have to stick to composite, there is also an alternative in form of tv tuners (in all sorts of shapes: isa, pci, usb, pcmcia, standalone) that in most cases have a composite input.
 
Thanks for the reply.
Yes, I'm stuck with composite. My collection of old machines date from the 70's and very early 80's where composite output was the norm.
If I understand your description of an alternative solution correctly, then I think that means I would need a modern(ish) computer in the mix. Actually I do have some hardware to bring composite signal into my Macbook Pro, but that's not what I want to do. I don't want to have to rely on my modern computer at all, thats why I was thinking of this stand alone solution to convert composite directly to VGA.

Of course I do have some nice composite CRT monitors too, but that take up too much desk space.

Phil
 
Actually the standalone tuner tv boxes work without a computer. I use the computer-connected model because no standalone box/converter can for example display at 100Hz (and it's very hard to find one that does 85Hz) and 50Hz on a CRT screen is a no-thanks for me ;)
 
I've used these boxes to take VGA and go to composite and S-Video (we actually use them to run power-point slide shows for local origination channels at the cable company I work at).

Quite the ghetto solution, but works very well for the purpose so long as cabling is shielded and kept to a minimum length. Look closely and ensure that they've a good return policy - I've used at least 5 different models of these types of units, including one that looks exactly like this one (but who can tell if the electronics are the same). Of the ones I've used, all would take VGA as input and output Composite/S-Video and pass-through VGA. None would take Composite/S-Video input and output VGA.
 
Hi Phil.

Yes, I've got one of these devices. Not the model you show but similar. Inputs composite video and S-video into VGA. I've found it works fine. In my case it goes into an old LCD screen so it's not so good for using with those arcade games. They can be streaky. Thats more a function of an older LCD screen than the converter device though I think.

Tez
 
How well does this work with 80-column text? A lot of these devices are made for security camera applications. Makes me wonder if it would be like trying to run 80-column text on an old TV.
 
tomasont said:
How well does this work with 80-column text? A lot of these devices are made for security camera applications. Makes me wonder if it would be like trying to run 80-column text on an old TV.
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Quite badly if used with composite video. One needs to use a "color killer" to suppress the chroma signal to eliminate color fringing. The cheap sub-$100 upscalers rarely have advanced comb filters (separates chroma and luminance signals from composite video) or decent quality scalers.
 
njroadfan said:
Quite badly if used with composite video. One needs to use a "color killer" to suppress the chroma signal to eliminate color fringing. The cheap sub-$100 upscalers rarely have advanced comb filters (separates chroma and luminance signals from composite video) or decent quality scalers.
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It depends a lot on the quality of the composite video you're putting into it. My Atari 520ST is the only computer I have which can actually display readable, streak-free 80-column text through its color composite output. (Obviously the clarity is only marginal at best, but it is actually readable and the colors are accurate, even on a 1981-vintage Amdek Color I monitor.) Other computers cannot, and usually cover up the problem by killing the chroma burst as soon as you switch into 80-column mode.
 
Thanks for all the replies. I just ordered one of these units so I'll let you know how it works out.

Cheers
 
Well it arrived, it works, but the image is VERY bad. Not really usable at any level. Back in the box it goes until I can find another use for it.

Phil
 
Just out of curiosity, how well does it work for it's stated purpose? Do you have a VCR or DVD player you can hook up to it?
 
This is the one that I've seen recommended time and time again for arcade rgb, Atari ST, etc. It doesn't do composite input, but it accepts component (w/ adapter), 9-pin RGB (w/ adapter), and 15-pin RGB, outputing both true 16:9 up to 1366x768 and true 4:3 up to 1024x768.

I haven't used it myself, as the price is a bit of a put-off. That said, I've spent nearly so much trying to find the "perfect" solution prior to just getting an NEC Multisync, so I guess I could've just saved myself the trouble and bought the ambery unit, hmm? :)
 
I'm also looking for such a composite-VGA solution - came across that Ambery unit when searching earlier, and it looked promising. Like Maverick1978, I was also put off by the price on it.
I'm also looking for something which can convert Apple IIgs RGB video to VGA, which I believe is a bit challenging as its scan rate is quite low. I don't remember now but I think there is some reason why the Ambery unit won't work with a IIgs.
In any case I too am interested in the holy grail-esque adapter which can do anything-to-VGA.
 
gubbish said:
I'm also looking for something which can convert Apple IIgs RGB video to VGA, which I believe is a bit challenging as its scan rate is quite low. I don't remember now but I think there is some reason why the Ambery unit won't work with a IIgs.
In any case I too am interested in the holy grail-esque adapter which can do anything-to-VGA.
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The Ambery unit should work in theory. The IIgs outputs 15.75khz RGB. Most use the "Highway 100" SCART RGB to VGA adapter. Its pricy but guaranteed to work. For the "all-in-one" adapter, consider the Micomsoft XRGB line of upscalers. Yes, they are very expensive and only sold in Japan, but they do the job. I personally own a Micomsoft XRGB2plus and can confirm that it works on the Apple IIgs. 2nd best and more all purpose (targeted for home theater market, not so much computer/game system use) is the DVDO Edge Green. I haven't read any reports of it being specifically tested with the IIgs, but it does have some problems with edge ringing due to an aggressive sharpness filter on 240p content (details at below link).

More info on the subject can be found here (click the link up top for other reviews): http://retrogaming.hazard-city.de/
 
Thanks, the XRGB looks quite interesting, if expensive..

Just did a quick search and it looks like the Ambery converter does work with IIgs and other such low horizontal scan rate video. Although it looks like there are some issues with the video quality in that setup.
I imagine that in order to convert from ~15khz line frequency to ~31khz, you would need to sample 1 video line worth of data over 1/15000 of a second, and output it at double the rate to generate ~31khz. If this is true, then the video quality would be largely dependent on the sampling rate and the quality of the A/D conversion.
Among all the techies here I bet we could come up with a good, cheap design to display vintage computer video on VGA monitors..
 
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There's a blog article out there:

http://damntechnology.blogspot.com/2008/08/apple-iigs-rgb-video-to-component.html

Which references an RGB-to-Component Video "kit" that supposedly does a fair job. Just about any new TV offers Component video in, so if using a modern TV instead of a VGA monitor with your IIgs is acceptable...

(There also schematics for similar devices floating around "in the wild" that aren't behind a paywall. Here's one, for instance:

http://www.keohi.com/keohihdtv/interfaces/diytranscoder.html

the article says he's used it for VGA, which is "480p", but looking at it I don't see any reason it wouldn't necessarily work with a IIgs since TVs support "480i", functionally the same scanratewise as the "240p" of the IIgs.)
 
Eudimorphodon said:
the article says he's used it for VGA, which is "480p", but looking at it I don't see any reason it wouldn't necessarily work with a IIgs since TVs support "480i", functionally the same scanratewise as the "240p" of the IIgs.)
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Like many vintage computers, the IIGS is actually putting out 525-scan line, interlaced NTSC video. Of those 525 scan lines, only 480 are visible, so when converted to digital, it becomes "480i". And the Apple II series does not use interlacing, so it simply duplicates the upper and lower fields, so you basically end up 30 progressive frames per second being outputted as 60 interlaced fields per second, to fit the NTSC standard. This also effectively doubles the vertical resolution, so the monitor sees the 640x200 resolution as if it was 640x400, with an extra 40 lines of the border area on the top and bottom.
 
vwestlife said:
Like many vintage computers, the IIGS is actually putting out 525-scan line, interlaced NTSC video. Of those 525 scan lines, only 480 are visible, so when converted to digital, it becomes "480i". And the Apple II series does not use interlacing, so it simply duplicates the upper and lower fields, so you basically end up 30 progressive frames per second being outputted as 60 interlaced fields per second, to fit the NTSC standard. This also effectively doubles the vertical resolution, so the monitor sees the 640x200 resolution as if it was 640x400, with an extra 40 lines of the border area on the top and bottom.
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Well.... kind of. 240p (59.94fps) is a bit of a hack, at least with composite/s-video output (its certainly not "broadcast safe"). Its a non-standard NTSC signal that eliminates the half scanline at the beginning and end of the raster to eliminate the offset between the interlaced fields (both fields are "on top of each other"). So in the end its only half the resolution of standard video, but progressively displayed. Its important that an upscaler detects this, because otherwise its treated as 480i and needlessly de-interlaced (which adds flickering and other artifacts along with the loss of smoothness in motion).

http://en.wikipedia.org/wiki/Low-definition_television (third paragraph)
 
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