atari 800 monitor jack to modern TV: problem

[rigaTONY]

Hello, I've recently followed this tutorial: https://www.youtube.com/watch?v=CwomI7iGD3w to make a 5din monitor jack to RCA video/audio jacks so that I can use the best possible signal from my Atari 800 onto my (modern) TV. Trouble is that, while the audio works fine, the video appears only in monochrome (black and white) using this method. It's certainly a clearer picture than the usual RF jack, but disappointing due to lack of color.

Can anyone suggest what I might have done wrong?

My tv is working fine when I plug in the dvd or anything else into the same jacks.

All advice is greatly appreciated.

 

Sincerely,

rigaTONY

[Bryan]

If you get B&W then you're probably using the Luma pin, not the Composite Video pin.

 

[Rybags]

By default the 800XL doesn't have the chroma signal connected at all to the monitor port. So your cable is probably fine but you need to do an addition inside the computer.

 

http://biosrhythm.com/?p=1002

http://www.verycomputer.com/10_016acd55e65c0d39_1.htm

 

There used to be a page with better instructions but I don't think it exists any more.

Note that it's suggested a 100 Ohm resistor be used inline.

[Bryan]

By default the 800XL doesn't have the chroma signal connected at all to the monitor port. So your cable is probably fine but you need to do an addition inside the computer.

 

1. He's using an 800 which has all the signals.

 

2. It looks to me like he's just doing comp. video.

 

Otherwise, the TV probably isn't happy with the Atari's signal.

[rigaTONY]

Ok, so I checked the wiring and you were right! I now fixed and connected to the composite video. However, the image quality is pretty bad, there's strange red colors in the white text of the memo pad, and the blue background is not right.

I've attached a link to the screen shots comparing the monitor cable to the rf jack:

 

https://www.flickr.com/photos/[email protected]/shares/w5Q9o6

 

Is this just a bad soldering job on my part, or something else?

 

Any advice is GREATLY appreciated, as I want to resurrect my Atari very badly.

Edited January 30, 2016 by rigaTONY

[Rybags]

Some modern TVs just don't work well with older gear.

 

The "best" signal you possibly get from a stock machine is using Chroma and Luma seperately aka S-Video.

Worst is RF/antenna port, Composite sits in the middle.

[ACML]

Composite will be no better than RF on an NTSC system. You want to go separate video Y/C or in a combined connector S-Video, Get one of these cables:

https://www.8bitclassics.com/Atari-800-XL-XE-5-Pin-DIN-S-Video-Cable.html

If you have an S-Video input, just plug it in and you wil get a great picture.

If you no longer have an S-video device, get the cable above and get this:

http://www.amazon.com/Etekcity%C2%AE-Composite-S-video-Converter-Upscaler/dp/B00B2B9Z20/ref=sr_1_1?ie=UTF8&qid=1454165660&sr=8-1-spons&keywords=etekcity+S-video+to+HDMI&psc=1

 

Edited January 30, 2016 by ACML

[fujidude]

Composite will be no better than RF on an NTSC system. You want to go separate video Y/C or in a combined connector S-Video, Get one of these cables:

 

I disagree with that. While it may be true that composite isn't any better in resolution than RF, the signal is cleaner. NTSC RF is essentially a composite signal turned into a modulated NTSC TV signal, and then converted back to composite within the TV's tuner. Eliminating that side trip can only help.

Edited January 30, 2016 by fujidude

[rigaTONY]

My TV has hdmi inputs, and jacks per the attached photo link here:

 

https://www.flickr.com/photos/[email protected]/shares/NHwr07

 

Sorry, I'm not to experienced at these details. Is this capable of "separate video Y/C"?

If so, should I change the soldering around in my cable, or should I just buy the cable from 8bit classics and get an s-video converter? What's best?

[Joey Z]

My TV has hdmi inputs, and jacks per the attached photo link here:

 

https://www.flickr.com/photos/[email protected]/shares/NHwr07

 

Sorry, I'm not to experienced at these details. Is this capable of "separate video Y/C"?

If so, should I change the soldering around in my cable, or should I just buy the cable from 8bit classics and get an s-video converter? What's best?

no

[ACML]

My TV has hdmi inputs, and jacks per the attached photo link here:

 

https://www.flickr.com/photos/[email protected]/shares/NHwr07

 

Sorry, I'm not to experienced at these details. Is this capable of "separate video Y/C"?

If so, should I change the soldering around in my cable, or should I just buy the cable from 8bit classics and get an s-video converter? What's best?

What you have is "component" video which is technically better than Y/C separate (S-Video) and they are not compatible. You could buy an S-video to Component (3 cable) converter, but you might as well just get the S-Video to HDMI since HDMI will likely be the standard for years. The 130XE video circuit does not convert well to HDMI. I have used the converter I linked to with an 800 and a 1200XL with great success. Someone tried that unit on a 130XE and did not like the result.

[Bryan]

Just a quick rundown of TV signals:

 

RF: Lowest bandwidth and noisiest picture. Picture will appear softer and will probably have some degree of moving patterns in it. This is basically Audio and the Composite Video signal fed into a radio circuit.

 

Composite (Yellow RCA): This is brightness (B&W) and color mixed together. The color is encoded as a waveform (phase-shifted sine wave) in the picture and is separated by filters in the TV. This process is not 100% accurate so the edges of objects on the screen will take on some color 'errors'. That is, the text will appear semi-colored. The Apple II is a particularly bad offender in this regard.

 

http://olduse.net/img/appleshot.png

 

S-Video (Y/C, 4 pin mini-DIN): Brightness and Color are never combined. This preserves the edges of text and allows for more bandwidth/sharpness in the brightness domain. Color is still encoded as a sine wave which limits the speed at which color transitions can occur.

 

Component (YUV, 3 RCA plugs): Color is not encoded as a sine wave and so it's bandwidth can be as high as that of brightness. This allows similar quality as one could get using RGB.

 

HDMI: Video is digital.

[rigaTONY]

So, 2 questions.

 

1. Just curious: can the Atari 800 be made to export true component video?

 

2. Since my specific TV doesn't have an S-Video port, at this point it's just best for me to get this S-video cable (referenced above), plug into an S-Video-to-HDMI-converter-box, and output to my tv's HDMI port?

[Bryan]

So, 2 questions.

 

1. Just curious: can the Atari 800 be made to export true component video?

 

2. Since my specific TV doesn't have an S-Video port, at this point it's just best for me to get this S-video cable (referenced above), plug into an S-Video-to-HDMI-converter-box, and output to my tv's HDMI port?

1. Not easily. The graphics chip puts out signals intended for S-Video and Composite. The color is already wave-encoded.

 

2. You will most likely see a big improvement with S-Video, especially if your TV isn't handling the Composite very well.

[rigaTONY]

Ok, I purchased one from: https://www.8bitclassics.com/Atari-800-XL-XE-5-Pin-DIN-S-Video-Cable.html

The composite video works great. My home-made cable is obviously at fault and I'll keep my day job instead of soldering electronics for a living.

Strangely, I tried on another monitor that has S-video input, and it's definitely not as good as the composite. So, I'll stick to composite.

Many thanks to all.

[Bryan]

That's odd. S-Video should look much sharper.