Using a Composite to VGA Converter for the Apple II

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Joined: Jan 15 2011
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I took a look at 3 inexpensive composite to VGA converters, and reviewed how they work for the Apple II.

I welcome comments about your own experience converting to VGA.

Composite to VGA for Apple II

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speedyG's picture
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Joined: Nov 16 2011
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Re: Using a Composite to VGA Converter for the Apple II

Hello akochera,
i have the same small converter without the written label on the top and i have been using that one with the ZX81, the Apple II europlus, the Apple IIe and the Apple IIGS in connecction with a 19" Flatscreen ...... - at the other hand i also use the same computers with the Phillips CR8810-II RGB Monitor. The comparision showed to me, that the Phillips RGB-Monitor beats everything that i have seen within the last 30 years - but for those who search for an alternate chance to display color-pictures from the Apple on Monitor - that converter is a acceptable and usefull alternative.....

Only with the IIGS the converter had recognizable weaknesses in the outlines of color-figures by speading the borders in different single colors.... this problem did not occur with the Apple IIe or the IIeuroplus. If i had to value the quality i would - in compare to the RGB-Monitor from Phillips valued as 100% - give to the converter still something around 85% to 90 %.

Some additionel remarks: it seems that the first one ( which you call the 5 Button-version ) which has the buttons for: Input ( select either Composite or SVGA ) - Menu ( to select Modes ) - Freeze ( to stop at 1 picture ) - Resolution ( to select between 40 Char Display or 80 Char Display ) - Wide Screen ( to adapt to Widescreen VGA ) probably was valued by you so bad in Textmode, because you probably forgot to switch button 4 when you switched the Apple with PR#3 to 80 col mode but probably left the converter in 40 Col mode.....

though the second one tested has 6 buttons instead of the other one with 5 buttons it would be interesting to get info on the labeling of the 6th button..... and the fact that instead at the one with 6 buttons the PowerOn LED was not inserted on the PCB and the hole for the LED was closed with the Label does not realy indicate that this box was manufactured in another way by another company..... in Fact the internal PCB seems ro be the same - but just optionaly populated with slightly diferring components.....

I´m not that sure that the second one is really not able to diplay color - but i believe that this is more dependent to the used input.... up to my experiance using the SVGA input normally causes a monochrome display that is more crisp but with no color - while using the component video input results with less crisp display but instead at least displaying the colors....

If it turns out that the second box really is having a problem with the colors it might be caused by tha fact that one converter is designed for use with PAL decoding while the other one is designed for use with NTSC-decoding.... ?

The 2 small black-boxed-converters that you display in your video - as well as the converter used by me ( also without the printing on top of the case - the first one you used in the video ) seem to be manufactured by exactly the same company in China. They have same size and lineout of the plug-connectors and i guess the one i don´t have to work also with external 9 Volt DC supply. I bought my converter several months ago at ebay for something like 39,00 Euros and mailing - so the amount in summary was 45.00 Euros.

sincerely
speedyG

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Re: Using a Composite to VGA Converter for the Apple II

speedyG wrote:

Some additionel remarks: it seems that the first one ( which you call the 5 Button-version ) which has the buttons for: Input ( select either Composite or SVGA ) - Menu ( to select Modes ) - Freeze ( to stop at 1 picture ) - Resolution ( to select between 40 Char Display or 80 Char Display ) - Wide Screen ( to adapt to Widescreen VGA ) probably was valued by you so bad in Textmode, because you probably forgot to switch button 4 when you switched the Apple with PR#3 to 80 col mode but probably left the converter in 40 Col mode.....

Thank you for your detailed reply! I tried your suggestion, but unfortunately it made no difference. The effect is to switch the output resolution from 800x600 to 1024x768 to 1280x1024 (and with various 60mhz or 75mhz). For practical purposes, however, the box is not translating the composite into enough detail to make those various modes useful. It stays blurry and unreadable in 80 column mode no matter what button I push.

speedyG wrote:

though the second one tested has 6 buttons instead of the other one with 5 buttons it would be interesting to get info on the labeling of the 6th button..... and the fact that instead at the one with 6 buttons the PowerOn LED was not inserted on the PCB and the hole for the LED was closed with the Label does not realy indicate that this box was manufactured in another way by another company..... in Fact the internal PCB seems ro be the same - but just optionaly populated with slightly diferring components.....

The six buttons are: zoom (looks like widescreen selector), av/sv/vea (input selection, av is the composite), PIP (picture in picture?), mode (preset soft/normal/bright/user), menu (user selectable brightness/contrast/ect), and PP (output resolution). I've tried many different combinations but makes no difference with color.

Whether the boxes are made by different companies, I cannot say. Probably not important. They are DEFINITELY different versions. They convert from composite to VGA very differently. I agree however that the plastic shell certainly uses the same mold.

speedyG wrote:

If it turns out that the second box really is having a problem with the colors it might be caused by tha fact that one converter is designed for use with PAL decoding while the other one is designed for use with NTSC-decoding.... ?

That's possible. The five button box is autodetect, and the 6 button version I lost the manual. All these were purchased from U.S. sellers (U.S. is NTSC), but of course the seller may not have known.

I mentioned in the video that I had tried two of the HD Gamebox (which can't deal with Apple II at all), but did not mention that I also tried two of the six button version, also from different U.S. sellers. This happened when I first ordered the five button version, but was mistakenly sent a six button version. Thus I was able to try two of the six buttons and confirm that they operated the same (that is, we are not dealing with a defective unit, unless both were coincentally defective).

Over on comp.sys.apple2, I received a reply from someone suggesting that difference is in how the luminance is filtered. Apple II apparently uses a higher bandwidth than the NTSC standard, and if one filters to the conventional NTSC bandwidth you lose a lot of the information required for sharp text. That poster also suggested that a more expensive converter (or an LCD TV with a composite input) might not perform any better, depending on whether it also filters for expected NTSC range. [I paraphrase as best I can, me not technical!] This all argues for a dedicated VGA card designed specifically for the Apple II....

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Re: Using a Composite to VGA Converter for the Apple II

Hello akochera,
i agree to all the stuff you issued now.... in fact the only point where i was a little offside with my opinion was the judgement to the 5 button box... as explained i have all computers from european market and therefor all were designed to PAL ...

this seems to force better transformation... PAL-output gives rather crisp textoutput.... my privite guess is that this is caused by the fact that the related conversion chips (TDAXXX ) are manufactured by german/french chip manufacturer ( SGS/Thompsen ) ......
In fact i have now just bought a few weeks ago a US-board of the IIe and if it is finished in mounting and assembling together in an empty case and supported with a good powersupply i could test that one with my PAL-version one.... and foind out if there is realy a difference...

but in fact due to the kind how the picture display is generated by the Apple II-series ( anyone from II, II+, IIe or IIGS ) there won´t be a chance to get a better VGA than it is generated with such converters....

even if a card would be designed it would result to a interfacecard, that just does a pickup of the videosignal from the internal videopin and thereafter puts that signal into the converterchip the same way its done at the external converter and the outputsignal taken from the converterchip to be issued to a plugconnector....
the only difference would be a better the shorter path instead of a probably longer cable....

and that is a common problem... i had 2 cables each 7,5 meters VGA from computer to a beamer... the one was cheap and badly shielded with bad result in beamerdisplay ... the other one cost 3-times cost of the cheap cable but the beamerdisplay was "lightyears" beyond of the one with the cheap cable.... so the best rule to get crisp display will still be : use as short as possible cables with good internal shielding.....

sincerely
speedyG

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In early days I had a lot of money but no time - now I have no money but a lot of time....
the second part includes less friends but a lot more joy on life....

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Joined: Oct 9 2011
Posts: 633
Re: Using a Composite to VGA Converter for the Apple II

I have the one with the "text" on top and can confirm it does not do color correctly. I actually bought it because the Apple-1 video won't sync to my portable Epson projector that I use for demonstrations. By converting it to VGA it works with the projector. Since the Apple-1 is B/W no big deal and the crisp text is needed. I did try it on my II plus and it doesn't work right with color, just some bleeding. I was going to hack the color killer not to work thinking it may have something to do with that but I never got around to it. I'm glad to hear there is a version that may work, so I may keep my eye out. after this posting, it has me thinking again... I may drag my II plus down to my home theater to see what my HD Projector does with the signal.