My apple II NTSC 1 is not working with my vga converter HD gamebox 1920x1200

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My apple II NTSC 1 is not working with my vga converter HD gamebox 1920x1200

My apple IIe is not working with my vga converter HD gamebox 1920x1200
(the converter works wonderfully with my commodores)

from time to time I get a very bad image (blurred)
most of the time nothing usable

once the converter is connected the apple II does not reply to reset
I'm using a usb to apple IIe converter (normally works wonderfully)

any idea ?

thanks

works sometimes wonderfully with my cvbs to hdmi + hdmi to vga but sometimes the image is blurred

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Re: My apple II NTSC 1 is not working with my vga converter ...

Apple video generation is finicky on both the Apple-1 and especially the Apple II line (I noticed you posted about your replica-1 also, which isn't an Apple-1, but may have similar issues even though it's a work alike and not the same video generation circuit)

Their video isn't quite perfect NTSC and the digital circuits in your converter just maybe losing sync. It took me a couple of tries on eBay to get a composite to VGA converter that would work and work in color with my Apple II.

For the Apple-1 video circuit, I have an Epson projector that won't accept the video feed, but will accept it converted to VGA. That projector is 14 or 15 years old so it's not modern video circuitry and should have worked. Yet my current HD projector in my theater can sync no problem to both the Apple I and Apple II video on its own.

So you never know...
I know that only explains what might happen and is not a solution, but the only solution may be to try differnt converter boxes till you find one that works.

Cheers,
Corey

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Re: My apple II NTSC 1 is not working with my vga converter ...

Hello dvador,
though the page is in German language it might be interesting to you:
http://www.appleii-box.de/H003_FBASSYNCLIB.htm

The topic is endless.... most computers in the beginning 80´s had problems with the video output...
most computers of the beginning area had a very specific dealing with the MTSC standards and did not allways match completely with the standards, mostly related to bad sync signals of the videosignal generation....

The page contains various contributions from former Garman computermagazins related to the topic,
among them circuitplans for splitting off the symc signal, making a better sync signal, adding
a video input to a tv-set and similar projects.... some of them solved the issues of those days quite well...

speedyG

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Re: My apple II NTSC 1 is not working with my vga converter ...

I'll try to read the article and check the signal

the hd gamebox 1920x1200 really solved the problem with my PAL commodore...
I expected a small miracle with the Apple Smile

my cvbs to hdmi + hdmi to vga produce an image sometimes of really good quality / sometimes blurred.

just by moving a finger above the IOU (without touching it), I loose the vertical synchronization

thanks

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Re: My apple II NTSC 1 is not working with my vga converter ...

Hi Corey,

Which composite-to-VGA converter did you end up buying? Do you know if they are still available on eBay? There seem to be quite a few, and I'd rather "guess" correctly the first time.

Thanks in advance for any info!

-Chris

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Re: My apple II NTSC 1 is not working with my vga converter ...

Using a composite to vga converter box with an Apple II is completely the wrong approach. The Apple II indeed does not output a proper NTSC signal.

Apple decided to cut costs by not adding the right chips to the Apple II motherboard to conform to the NTSC standard because they realized that by using an RF modulator, the picture you can get on a TV set would come out more or less the same.

But even with an RF modulator, the picture output is really bad.

There are several ways to get a good picture out of an Apple but I won't list them here unless asked due to the fact that I have tried a lot of them and they have already been heavily discussed.

I would even question the idea that you can get a proper signal on an LCD monitor due to the fact that there are too many differences on how they both work. I have not tested the differences, but text output is fine...

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Re: My apple II NTSC 1 is not working with my vga converter ...

I took a guess with my adapter. However I can tell you both my circa 1998 Sony plasma and my 2013 Samsung LED TVs work fine with the Apple II. This is not the case with all flat screens. So even with a TV, you need to take a guess and be prepared to exchange it. It took me 2 TVs last year to get one supported by the Apple II and the Apple I video.

Good luck,
Cheers,
Corey

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Joined: May 27 2013 - 13:01
Re: My apple II NTSC 1 is not working with my vga converter ...

Well, it is not as if it is completely impossible that any TV with composite input would never work with an Apple II. What I am saying is that it is not the norm. Recently, at the last Kansasfest, an LCD tv was found that seems to work fine with an Apple II. A lecture was given about it on how to use that particular model of TV to make the Apple //c more portable.

What we are dealing with here is the absence of the Apple II being completely NTSC standard, and some TV manufacturers who make their composite inputs not care about the messed up signal of the Apple II.

Back in the day, I used the RF modulator on my VCR for the Apple II and I recorded the output of an Apple II onto a VHS tape. The quality of the output was not great but viewable.

I will put it this way:

If the output composite signal of a device holds to the NTSC standard, then it will work properly with ANY device that has composite input. If the output of a composite signal of a device does NOT hold to the NTSC standard, then it may or may not work properly with a given device that has composite input, although it usually won't. Do things right, and you'll be all right. Do things wrong, and you roll the dice.

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Re: My apple II NTSC 1 is not working with my vga converter ...

I have instead used the possibilty to take signals from RGB Card and adjusting it correct to a RGB to VGA converter.
By this the poor and not completely compatible sync signals of the Apple can be avoided and the picture gets instead its sync signals from the converter chip. Then the only problem is a good adjustment once to the left side of the picture.... ( vertical sync ).
speedyG

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Re: My apple II NTSC 1 is not working with my vga converter ...

This has been done in the past (RGB) with an apple RGB monitor or conversion. But some people have complained about the RGB signal even though it is supposed to be superior. Especially the Apple IIGS RGB handling of some Apple 8 bit games.

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