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Bryan

New video upgrade coming soon!

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That's a different way to get the audio than I did.

Both TIA and POKEY sound are at the bottom of the 2 resistors (side facing the console's front), left of the tall red coil.

I bridged a .1uf electrolytic cap and wired to the center of the audio, and ran ground to the large area where the RF was.

Here's a halfway installed pic. All signals can be found above that small left-most IC xx74LS32x. Some at the thru holes in front of the resistors, and the rest at the resistors.

attachicon.gifimage.jpg attachicon.gifimage.jpg

I still think a resistor needs pulled because composite is fuzzier than it should be.

The PAL install above had a resistor removed. like I already said, no hurry as SVideo is spectacular. Just in the future composite is convenient to have when travelling.

 

S-Video: attachicon.gifimage.jpg

 

Yeah i noticed there's a few ways to pull the dual audio. I pull top of c10 (pokey) and bottom c14 (tia) with a 47k ohm resistor tied to line out. As for composite, i skipped it as i feel the difference is too big to even bother. svideo or bust lol

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I just purchased an Atari 400 off eBay. It hasn't arrived so I don't know yet if there was any video mods done to it yet (forgot to ask).

 

A couple of questions.

1) This board goes into the 4050 socket -- does the 4050 go into the daughter board somewhere, or is piggybacking required if I want RF output as well.

2) On the 400, no additional changes are required to the board

3) Is there an existing hole to route the new composite / s-video outside the machine, or do I need to modify the case.

4) How do you recommend getting audio out?

 

Thanks in advance.

 

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I just purchased an Atari 400 off eBay. It hasn't arrived so I don't know yet if there was any video mods done to it yet (forgot to ask).

 

A couple of questions.

1) This board goes into the 4050 socket -- does the 4050 go into the daughter board somewhere, or is piggybacking required if I want RF output as well.

2) On the 400, no additional changes are required to the board

3) Is there an existing hole to route the new composite / s-video outside the machine, or do I need to modify the case.

4) How do you recommend getting audio out?

 

Thanks in advance.

 

 

1) You can piggyback the upgrade onto the 4050, or you can replace it completely with the mod

2) No changes to the motherboard but you will need to solder a single wire to it (for the Video mod specifically - Audio is not addressed here)

3) No existing hole, you will need to route wiring through the shield and then modify the case for whatever jack you use

4) You can pull audio direct from POKEY if you don't mind losing the SIO sounds, otherwise there would need to be some additional work (There is a potential upgrade in the works to address this specifically for the 400)

Edited by orpheuswaking

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Succes!

 

Before and after pictures.

 

Atari 600 XL PAL.

 

It didn't remove the noise pattern, which moves from the bottom of the screen to the top. I believe that is due to a hardware fault / bad design in the 600 XL.

 

http://imgur.com/a/A8DW2

Edited by dakidski

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Succes!

 

Before and after pictures.

 

Atari 600 XL PAL.

 

It didn't remove the noise pattern, which moves from the bottom of the screen to the top. I believe that is due to a hardware fault / bad design in the 600 XL.

 

http://imgur.com/a/A8DW2

What kind of power supply are you using with that machine?

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Succes!

 

Before and after pictures.

 

Atari 600 XL PAL.

 

It didn't remove the noise pattern, which moves from the bottom of the screen to the top. I believe that is due to a hardware fault / bad design in the 600 XL.

 

http://imgur.com/a/A8DW2

Try plugging it into a different outlet or change surge protectors too.

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Silly me!

 

I can now hook up my 600 XL with the s-video cable, instead of being forced to comsposite only.

 

The picture is flawless!!

 

Wow! Thanks Bryan!!! Now I can sell off those ugly XE-models. :)

 

Photos taken in direct sunlight, but they still show the 600XL with a superb picture: http://imgur.com/a/0JOCU

Edited by dakidski

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Silly me!

 

I can now hook up my 600 XL with the s-video cable, instead of being forced to comsposite only.

 

The picture is flawless!!

 

Wow! Thanks Bryan!!! Now I can sell off those ugly XE-models. :)

 

Photos taken in direct sunlight, but they still show the 600XL with a superb picture: http://imgur.com/a/0JOCU

Ha, i'm surprised you even added composite!

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Ha, i'm surprised you even added composite!

I was caught in the old mindset: 'PAL 600XL can only do composite.' I actually purchased UAV in order to improve this composite, but then all of the sudden yesterday night I was like: "hey wait... UAV can output s-video!?" So silly, lol.

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attachicon.gifIMG_5763.jpg

 

This is composite in an 800XL so ... which connections should I check first? Remember, I assembled this board from parts, so I'm thinking I may have a bad solder joint at one or more of the jumper block pins.

 

 

 

Looks like LUM3 isn't hooked up. The standard blue screen is a lum of 0x0A against background of 0x04. If you're missing the top bit, you get a lum of 0x02 for the text.

 

On the 800XL, LUM3 is pin 3 of the CD4050. The jumper that makes the LUM3 to Pin 3 connection is the 2nd one that goes across (looking at the jumper pictures, the 2nd jumper down).

 

Unexpectedly had a couple hours free this afternoon, so I spent part of it taking a look at last week's work. Turns out I had a solder bridge between two pins of the jumper block on the underside of the board, almost certainly from my goof in assembly order (I soldered in both rows of the socket adapter before I soldered in the jumper block - d'oh! That gives VERY tight clearances to solder in the jumper block pins). So I fixed the solder bridge, touched up and reflowed pretty much everything else just in case, and now get much better results. I wish I had an S-video monitor but this is decidedly better than stock even through my ancient Apple Color Composite monitor (circa mid-80's).

 

post-30400-0-77450600-1458335499_thumb.jpg

 

post-30400-0-14038300-1458335514_thumb.jpg

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I've been working on a new upgrade that can be installed in any A8, 5200, & even the 2600.

 

I know there's a million upgrades out there, but the good ones are mostly based on tweaks to the original Atari circuit, and the bad ones are haphazardly designed.

 

1st, the real problems with the Atari circuit(s):

 

The video circuits in most A8's are not sufficiently decoupled from the digital noise in the system. Video power and ground are often shared with very noisy components like DRAM and this causes vertical bars to appear in the picture. For example, you can often see the refresh cycles on the left side of the screen. Crude DACs like the one made from the CD4050 have no ability to reject power supply noise and will superimpose it on the picture. No tweaking of the video buffers will remove it. Atari actually put components in some XLs to blur the image in an attempt to clear up the lines.

 

That's not to say the buffers didn't need tweaking. They frequently deviated from the 75-ohm impedance standard that that meant the picture quality could be unreliable (shadows, smearing & ghosting), especially with longer cables. At video speeds, you only get maximum transfer when everything is the right impedance.

 

In addition, some of the chroma circuits produced highly distorted sine-waves which contributed to noise in the image.

 

So to solve these problems, my board:

 

1. Has an on-board regulator to create a clean video power source.

 

2. Has a 3-channel video amplifier designed for 75 ohm loads.

 

3. Has a pixel re-clocking circuit to remove skew and better align the 4 luminance signals into a perfect pixel edge.

 

4. Has a carefully designed chroma-shaping circuit.

 

In addition, there's an adjustable pot on the board which controls the phase between the chroma and luma signals. A nice side-effect of this that you can change the artifact colors. There's also a jumper to invert the chroma which swaps the positions of the artifact colors.

 

The board plugs into the CD4050 socket for easy installation on most machines. It can be used in place of the original circuit or along side it.

 

I'm working on the final board layout and I hope to have them available in the AtariAge store early next year. Here are some pictures of the prototype. Any patterns in the picture are due to the camera picking up the CRT mask, but you'll notice the absence of vertical bars (I'll try to get better pictures...). One of the pictures is taken off my LCD (and even the LCD is hard to photograph). The split screen pictures show the effect of artifact tuning. The board is currently installed in a very noisy 130XE. I'll try to get some before pictures.

 

I'm calling it UAV for Ultimate Atari Video. More to come!

Looks like a really cool idea.. I would like to get at least 2 to start with of this hardware board.

Thanks a Bunch!

Stephen J. Carden

http://www.realdos.net

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Unexpectedly had a couple hours free this afternoon, so I spent part of it taking a look at last week's work. Turns out I had a solder bridge between two pins of the jumper block on the underside of the board, almost certainly from my goof in assembly order (I soldered in both rows of the socket adapter before I soldered in the jumper block - d'oh! That gives VERY tight clearances to solder in the jumper block pins). So I fixed the solder bridge, touched up and reflowed pretty much everything else just in case, and now get much better results. I wish I had an S-video monitor but this is decidedly better than stock even through my ancient Apple Color Composite monitor (circa mid-80's).

 

Glad to hear it. It still looks kinda dark. Is that just the picture?

 

My assembly order is Config Jumpers, Socket Pins, Terminal Block.

 

Looks like a really cool idea.. I would like to get at least 2 to start with of this hardware board.

Thanks a Bunch!

Stephen J. Carden

http://www.realdos.net

 

Right now I'm in Costa Rica and not taking new orders. I am going to be making up a batch for the AA store soon. I just need to confirm a few things so I can make any last minute changes.

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It didn't remove the noise pattern, which moves from the bottom of the screen to the top. I believe that is due to a hardware fault / bad design in the 600 XL.

That's not a typical noise pattern. I'd definitely try a different supply for comparison.

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Glad to hear it. It still looks kinda dark. Is that just the picture?

 

My assembly order is Config Jumpers, Socket Pins, Terminal Block.

 

Just the photo - my monitor is completely analog and probably needs new caps to boot, but it works. I'm actually thinking of going back to my previous not-quite-as-old (2003) CRT TV but in the meantime, I like using Atari computers through a vintage Apple monitor, lol. Actually, I'd love to find a reasonably-priced Commodore 1702/1702 locally but that hasn't yet happened.

 

Yeah, I did Terminal Block, Socket Pins, and then Config Jumpers - I have no idea what I was thinking. The good news is it's working great and WAY better than stock. I'll definitely be picking up a second plug-in unit from the Store ASAP, and maybe even a third. Can't wait to see the output of my 2600 Woody after I install the bare board in it. Gotta figure out if I want to mount permanent AV jacks in the case, or just wire the board straight to a set of RCA cables out the bottom case opening ... My drill is currently kaput (either the charger is dead or both my drill batteries are) so I can't drill the case for jacks quite yet anyway. I guess that makes the choice easy for now.

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That's not a typical noise pattern. I'd definitely try a different supply for comparison.

Will do, but no way I'm going back to composite. I now have my dream Atari setup. 600XL is one of the best looking micros. And the picture is just great now.

Regards.

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I would like to order 1 or 2 for 7800 and 2600. Please let me know.,

Why can't you read the thread, these are not available for order now(see post# 463, only 5 posts back). Once Bryan makes more they will be available through the Atariage store.

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Why can't you read the thread, these are not available for order now(see post# 463, only 5 posts back). Once Bryan makes more they will be available through the Atariage store.

 

 

Ufff.....Someone is cranky....eat a sneakers, play a game, chill...:)

 

Let me know when they become available. Thanks!

Edited by alortegac

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Pardon my ignorance but 19 pages is a little hard to sift through when so many devices are being talked about. Did anyone try this on a 400 and have success getting audio-out? I am debating grabbing one of these when they become available again, but I'm nervous enough to be poking around inside my 400 much less trying to modify it to get audio-out.

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Pardon my ignorance but 19 pages is a little hard to sift through when so many devices are being talked about. Did anyone try this on a 400 and have success getting audio-out? I am debating grabbing one of these when they become available again, but I'm nervous enough to be poking around inside my 400 much less trying to modify it to get audio-out.

An optimal 400 audio solution is something I'm going to work on this week.

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An optimal 400 audio solution is something I'm going to work on this week.

 

You the man!

 

Seriously that would be awesome. I've been using my 400 more recently and a video upgrade was something I have been considering, but many of the other solutions out there require some pretty heavy modifications and that just makes me nervous on a 36 year old machine.

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You the man!

 

Seriously that would be awesome. I've been using my 400 more recently and a video upgrade was something I have been considering, but many of the other solutions out there require some pretty heavy modifications and that just makes me nervous on a 36 year old machine.

Even without the audio out the video upgrade is amazing. Technically you can pull audio off the pokey, but you wouldn't get SIO

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