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What converter(s) do I need to convert the Apple IIGS RGB output to HDMI?

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uyjulian

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Feb 11, 2014, 1:28:22 PM2/11/14
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What converter(s) do I need to convert the Apple IIGS RGB output to HDMI?
Composite looks blurry in hi-res mode (why?)

--
I has a Apple IIGS

Michael J. Mahon

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Feb 11, 2014, 6:53:57 PM2/11/14
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uyjulian <uyju...@gmail.com> wrote:
> What converter(s) do I need to convert the Apple IIGS RGB output to HDMI?
> Composite looks blurry in hi-res mode (why?)

Composite color is limited by standards to about 3MHz bandwidth, so you
won't get more than about 300 lines of horizontal resolution. That's
usually fine for game graphics, but it does appear blurred when viewed
close up. 80-column text is essentially unusable (which is why Apples
intended to be used with TV monitors only used 40-column text).

Conversion of IIgs RGB to HDMI is fairly complex. I'm sure someone here has
a recommendation.
--
-michael - NadaNet 3.1 and AppleCrate II: http://home.comcast.net/~mjmahon

Michael J. Mahon

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Feb 11, 2014, 7:04:52 PM2/11/14
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Michael J. Mahon <mjm...@aol.com> wrote:
> uyjulian <uyju...@gmail.com> wrote:
>> What converter(s) do I need to convert the Apple IIGS RGB output to HDMI?
>> Composite looks blurry in hi-res mode (why?)
>
> Composite color is limited by standards to about 3MHz bandwidth, so you
> won't get more than about 300 lines of horizontal resolution. That's
> usually fine for game graphics, but it does appear blurred when viewed
> close up. 80-column text is essentially unusable (which is why Apples
> intended to be used with TV monitors only used 40-column text).
>
> Conversion of IIgs RGB to HDMI is fairly complex. I'm sure someone here has
> a recommendation.

I should have pointed out that since the Apple video window is only 40
microseconds of the standard 52 microsecond horizontal scan window, so less
than 300 lines can be resolved within the Apple scan window.

RJ

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Feb 11, 2014, 7:47:27 PM2/11/14
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uyjulian wrote:
> What converter(s) do I need to convert the Apple IIGS RGB output to HDMI?
> Composite looks blurry in hi-res mode (why?)
>


I don't believe there is such a product out, if so, it would be costly for
that type of conversion.

If you want to use modern LCD TV, the only option is the Nishida Radio's
component rgb adapter. This will enable you to use any flatscreen LCD tv
(youtube has one shown on a 42 or 46 inch flatscreen tv) Quality is good
for the money spent, but compared to true RGB monitors, the RGB monitor
still wins out in crispness, and color clarity.

good luck in your search.


sicklittlemonkey

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Feb 11, 2014, 8:37:12 PM2/11/14
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On Wednesday, 12 February 2014 13:47:27 UTC+13, RJ wrote:
> If you want to use modern LCD TV, the only option is the Nishida Radio's
> component rgb adapter.

Not so ... choose a recent LED/LCD one with SCART, like this (randomly chosen on amazon):
http://www.amazon.com/LG-ELECTRONICS-28MN30D-MONITOR-READY/dp/B00F5MOHY8/

And order or make a SCART adaptor:
http://vintageware.orconhosting.net.nz/scart.html

I just did this - though using an older Samsung SyncMaster - and it looks great.

Cheers,
Nick.

RJ

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Feb 12, 2014, 5:36:56 AM2/12/14
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ah, yes I forgot about SCART. Where I am from, we do not use PAL. You guys
are very lucky to have SCART products!



sicklittlemonkey

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Feb 12, 2014, 5:51:50 AM2/12/14
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On Wednesday, 12 February 2014 23:36:56 UTC+13, RJ wrote:
> ah, yes I forgot about SCART. Where I am from, we do not use PAL. You guys
> are very lucky to have SCART products!

The monitor I linked to was on USA Amazon in the US!

SCART is nothing to do with PAL. The monitor I have handles NTSC, PAL, SECAM.

Cheers,
Nick.

uyjulian

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Feb 12, 2014, 10:42:22 AM2/12/14
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Any scart > HDMI converters compatable?

Eric Rucker

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Feb 12, 2014, 11:17:01 AM2/12/14
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The problem is that the IIGS video output tends to not hold up to protocol conversions all that well. SCART is a mere pinout conversion (although it only works with TVs that support RGB input), and component is a color space (but not protocol) conversion.

And, as far as I know, all of the 15 kHz RGB converters on the market go to VGA, not HDMI.

Michael J. Mahon

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Feb 12, 2014, 12:59:52 PM2/12/14
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That could work. How well with Apple IIgs video depends on the
implementation.

Antoine Vignau

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Feb 12, 2014, 2:24:34 PM2/12/14
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uyjulian

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Feb 12, 2014, 3:10:51 PM2/12/14
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VGA is fine (my TV has VGA also)

sicklittlemonkey

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Feb 12, 2014, 5:25:25 PM2/12/14
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On Thursday, 13 February 2014 09:10:51 UTC+13, Julian Uy wrote:
> VGA is fine (my TV has VGA also)

Someone on Facebook has recommended this one:
http://www.amazon.com/SCART-Video-to-HDMI-Converter/dp/B00G2157W2/

The problem is they've tried it with "many systems" but not the IIgs.

I would love to know ... the whole community is looking for solutions. : - )

Cheers,
Nick.

pitz

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Feb 12, 2014, 9:47:17 PM2/12/14
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I've tried with my IIgs and Roger's SCART cable and did not get anything on my TV. But I don't have any other SCART output device, so it's hard to tell if the adapter, the cable, or the HDMI conversion is defective.


sicklittlemonkey

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Feb 13, 2014, 12:37:32 AM2/13/14
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On Thursday, 13 February 2014 15:47:17 UTC+13, pitz wrote:
> I've tried with my IIgs and Roger's SCART cable and did not get anything on my
> TV. But I don't have any other SCART output device, so it's hard to tell if the
> adapter, the cable, or the HDMI conversion is defective.

Oh no. What model of TV? I would like to make a list of negatives too.

The cable is unlikely to be wired incorrectly, but you could use a multimeter (continuity tester) to verify the main mappings as listed by Roger:
http://vintageware.orconhosting.net.nz/apple2/scart.html

As long as R, G, and B video, and sync are connected you should see a picture if the TV has the SCART input selected.

The Samsung SyncMaster 940MG is what I use. (Also similar 740 models have been mentioned in this group.)

I posted composite vs SCART pics on Facebook:
https://www.facebook.com/groups/5251478676/10152650401843677/

This weekend I'll be testing on a Panasonic set.

Cheers,
Nick.

uyjulian

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Feb 13, 2014, 10:21:48 AM2/13/14
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Things... are getting pretty expensive here.
I'll hold off for now...
(btw I have a vga to HDMI converter)

sicklittlemonkey

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Feb 16, 2014, 6:49:39 AM2/16/14
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On Thursday, 13 February 2014 18:37:32 UTC+13, sicklittlemonkey wrote:
> This weekend I'll be testing on a Panasonic set.

The Panasonic TX-15LT2 is a nice little 15 inch set. Pics here:
https://www.facebook.com/groups/5251478676/10152660344213677/

I bought it for $25.

Cheers,
Nick.
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