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using Composite to VGA converters

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I never worried about it much on the TI, but when I was messing around on the Playstation, I used to write everything for 50hz. If the console was 60hz, it just dropped every 6th frame for an equivalent frame rate. ;)

 

You just have to be careful on a real 50hz console - they have more time in the vertical blank than NTSC, so if you are really pushing things during the blank you might right out of time when that code moves to 60hz. Not as big a concern going the other way. :)

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I might still have my PAL console that came over with me from the UK. It's in a bit of a state externally I vaugely remember. I last remember seeing it in the loft a while back, but if I can find it, it's yours.

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Thanks to all of you....as I've looked around and read several articles, I have a much clearer (no pun intended) understanding of the issues at hand.

 

it's frustrating that PAL consoles seem to fair better with these low cost converters than NTSC systems do. I've found countless pages of European TI users using the cheapest converter and having it work first time (exactly the opposite of what I read from North American TI users)...But there is no arguing that a $79 F18A ($92 CAD - Thank you OPEC) is cheaper than a $468 xRGB (a whopping $543 CAD). Especially considering the console cost me $100 including shipping and import fees!

 

It was encouraging to hear that I "might" luck into a cheap unit that works, but if I have to go through 2 or 3 to find one, then the F18A is still cheaper (and as someone else mentioned, provides other enhancements as well),

 

As always the AtariAge TI crew demonstrates a more finely tuned synapse-firing mechanism than I posess in such matters. I guess I've got to get myself a second console, keeping one stock, and making the other one a 1981 sci-fi hybrid by adding an F18A. In the interim, I found a sweet little 12" (13"?) Flat Screen (CRT) Trinitron for $10 on craigslist that I pick up next week, which will be far more practical than this honkin' 20" mofo I'm using now.

 

If I do break down and try another one of these converters, and find one that works, I will be sure to provide the sku in this thread.

 

I found my old PAL console. PM me if you're interested.

 

img_1229.jpg

 

img_1226.jpg

 

img_1230.jpg

 

Keyboard needs attention as it bounces on some keys

 

img_1225.jpg

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Is the only difference between a PAL and NTSC ti994a the VDP (and its supportive electronics) chip? I.e. the ROMS, GROMS etc are identical but the vertical irq just happens to trigger at 50/60 Hz depending on the VDP chip?

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I found a device that works...with a few caveats.

 

It is the StarTech.com COMP2VGA

 

I had already hooked my console up to my living room LED TV via le composite connector, and was pretty dissapointed with the picture quality. Well, the output from this device is about the same.

 

(the thumbnailed picture doesn't really reflect the muddy washed out image...in fact I WISH it looked this good in reality!)

 

First there is no hardware upscaling in the device so it passes the raw 256x192 image directly to the monitor, which applies it's own rudementary upscaling to the closest resolution available (640x480) which is already a pretty blurry rez on this monitor.

 

Further, after reading what I have on this topic, I'm guessing that the device is applying some kind of de-interlacing filter...which blurs the image further. (looks like that's what's happening anyway)

 

I reduced all colour channel (R G B) intensities to about 30% each, dropped the brightness and contrast (contrast is now at zero), and I've achieved a "tolerable" image. The best description would be to say it looks similar to Classic99's 2xSal filter, but with analog colour bleed artifacting (which looks gawdawful on an LCD).

 

Now what I haven't tried (since I no longer own such a beast) is hooking it up to a VGA CRT monitor...I'm guessing that THAT would be excellent, since CRTs are not "locked" to a particular "best" resolution and the scanlines would help lessen the effects of the colour bleed. I'll try to borrow one and see how I fair in that regard.

 

But if you want to connect a stock 4A to a VGA LCD monitor, and your unit has had problems doing so, this device WILL work in colour...

...you just might miss how much better your TI looked on a TV.

 

Looks like sticking with CRT's or installing an F18A will be my only options after all.

 

Guess I'm buying a second console.

 

 

post-40994-0-43477500-1420665111_thumb.jpg

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I have yet another solution, for probably $10 USD.

 

I had the same problem as the original poster--the output from a cheap AV-to-VGA converter was badly banded black & white. So I sold that eBay converter on Kijiji (for a profit--shhh,...), and used a $5 (eBay) AV-to-HDMI converter, in conjunction with a $4 (eBay) HDMI-to-VGA converter.

 

Double conversion works. The AV-to-HDMI converter does a better job of interpreting the raw signal captured from the TI-99/4A, (which was originally supposed to go to the modulator), than the AV-to-VGA had. The final output is somewhat washed and blurred, but nothing I consider serious. It is an easy solution which saves me having yet another output device on my crowded workbench. And of course it fits my primary criteria: cheap.

 

Ian

 

post-40144-0-53596900-1516221793.jpgpost-40144-0-36373800-1516221794.jpg

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That's an interesting solution! I recognize the AV2HDMI box, but which HDMI2VGA box are you using (as we know your pairing works--and with the cheap stuff, that ism't always guaranteed with a different pairing)?

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I don't think that part of the equation is the difficult one, as it's the AV-to-HDMI converter that is doing the "hard" work of digesting the improper AV signal. Once you have good HDMI I think it's clear sailing from there. But to answer your question,...

 

The HDMI-to-VGA is a "robust connector" type affair, which can be seen in my second photo, connected to the Mini AV2HDMI. It's black so somewhat hard to see. Here are a couple of better pictures. They can be had on eBay for 3 to 6 dollars or so. Note: try to get one with the audio output. Not all of them have that--then you pipe both video and sound into your existing monitor and computer speakers.

 

eBay examples at the time of writing, including but not limited to item numbers: 172695857361 122486456926 162736693760 You get the idea.

 

post-40144-0-36286500-1516512157.jpgpost-40144-0-04230900-1516512158.jpg

Edited by TMA-1
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https://www.pagetable.com/?p=672

 

I had a TI with the no color issue. I swapped out the crystal as mentioned in the above thread which fixed it. Add this info?

 

This is interesting. I wonder if this could also resolve problems with some modern monitors and converters synchronizing as the black-and-white photo looks identical. (Also, will be moving these two posts to a relevant thread when I dig it up...)

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Just to add more specific detail. The TI in question did show up as color when using an adapter cable to go to an LCD component input. The TI showed black and white when going through the RF modulator to a small CRT TV I have. The same RF modulator worked fine with two other TI's I have on the same CRT TV. So in my case, the crystal swap fixed a black and white via RF modulator to CRT problem.

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Just to add more specific detail. The TI in question did show up as color when using an adapter cable to go to an LCD component input. The TI showed black and white when going through the RF modulator to a small CRT TV I have. The same RF modulator worked fine with two other TI's I have on the same CRT TV. So in my case, the crystal swap fixed a black and white via RF modulator to CRT problem.

 

The issue of which I speak is similar otherwise in that some devices can synchronize and others cannot. It has been assumed to be related to the 240p problem, in which a device is expecting an interlaced signal but receives a progressive signal. Some devices will not show a screen, some devices will show black and white, and some devices will show the screen but treat it as interlaced.

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I found a recommendation somewhere around the Interwebs about a good composite to HDMI upscaler which handles our non-interlaced signal. While it is difficult to find, the Kanex Pro CON-AV-HD4k works perfectly.

 

Check out the Don't Mess with Texas megademo. The input signal to the Kanex Pro was standard TI composite with output at 720p @ 60Hz, scaled during capture to half the resolution to spare the CPU in my laptop and skip as few frames as possible, then resized to 320x240 to fit AtariAge upload limits.

 

"Don't Mess with Texas" captured from Kanex Pro CON-AV-HD4K

(Quick note: any freezing or skipped frames is my laptop CPU being over-whelmed in the capture process.)

Of particular impressiveness is this result:

 

post-27864-0-93881600-1551502379.png

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I found a recommendation somewhere around the Interwebs about a good composite to HDMI upscaler which handles our non-interlaced signal. While it is difficult to find, the Kanex Pro CON-AV-HD4k works perfectly.

 

How does it compare to the RetroTINK?

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If HDMI output is an option, I've had really good luck with this thing called a "Ratsmart" composite to HDMI converter.

 

(Edit... I have NOT tried it with a TI tho.. has anyone here?)

 

It's about 15 bucks shipped via eBay. It 's got a little switch on it to output either 720p or 1080p. Looks remarkably good for how cheap and simple it is.

 

If you really have to do real VGA, I remember the XRGB-2plus being an impressive and expensive solution. Haven't tried it with a TI tho. I used it on my Apple IIgs and it was the best solution I could find at the time (maybe 2006 or so).

 

(I think I still have it in the garage and would consider trading it... if anyone is interested send me a PM)

Edited by CaptainBreakout

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How does it compare to the RetroTINK?

 

I will test that out today and post results.

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How does it compare to the RetroTINK?

 

Output from the RetroTINK is 480p @ 60Hz. Comparing the results from this demo, I would conclude the RetroTINK as inferior. I would give the RetroTINK more testing as this test case may not be the target scenario.

 

"Don't Mess with Texas" captured from RetroTINK

 

At the flag girl demo, the individual modes are clearly visible.

 

post-27864-0-14630900-1551570111.pngpost-27864-0-36882400-1551570136.png

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One more thing to note is I do not test for latency. There might be some differences between the KanexPro and the RetroTINK which makes one better for playing games than the other. Provided a little more spare time I think I could do such testing.

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The latest firmware for my Onkyo TX-NR656 fixed the sync problem I was having with the KanexPro but it still leaves me without TI audio from the RetroTINK. And ONLY from the TI: when I switch to the NES the audio comes in fine, so I am perplexed.

Playing with the two tonight there are definitely pros and cons for each. In particular, I find the KanexPro smooths the edges of moving objects or objects which have movement around them. This is easily visible with Road Hunter on the TI and Ballblazer on the NES. This does not occur with the RetroTINK but it flickers a little to much for my liking. Also, the RetroTINK does not keep the video input setting between power applications and does not seem to like automatically finding the TI's composite, making me manually select with every use.

 

All said, both have purpose in my arrangement. The KanexPro will soon have a permanent home on my living room system and the RetroTINK will find itself in my travel kit.

 

A shout toward Hal, Jr., (hehehehe): still using that old MacBook for the Faire, the RetroTINK's 480p output will eat less CPU for streaming.

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At least going in through my Denon receiver then out to the TV, whether A/V ins through receiver or HDMI in via this https://www.amazon.com/gp/product/B0719G5TL9/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1, I got really bad snow and jaggies on text. Video on games was tolerable...Alpiner and Parsec looked ok. But the title screen, Basic, XB...anything text looked like crap. Didn't really see any difference b/t composite in vs HDMI in via adapter. I have not yet tried direct to TV. Wonder if the KanexPro would be any better, or if it's just that on a 65" 4K, there comes a point when small flaws are simply magnified too much. I ordered one of those 10.1" Raspberry Pi displays one of y'all mentioned. Figuring that may be more tolerable pre-F18A MK2

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