Atari 800 VS Commodore 1702 monitor

[polyex]

I bought a 5 pin DIN to 4 RCA jack cable on eBay for my Atari 800 (not an XL). With my Atari, if I hook the composite from this cable to a late 1990's vintage TV/VCR combo TV, I get a decent color picture (blue Atari Memo pad background). Recently I bought a Commodore 1702 monitor as I wanted to try and improve the picture for my Atari 800 by using the 1702's Chroma and Luma input jacks. Problem is I get a black and white picture on the 1702 when doing this with my Atari 800 using my cable. I then tried using the composite with the 1702 (the one that works fine with the old TV/VCR) and I still get a black and white picture! Thinking I might have a problem with my 1702, I hooked a modern DVD player to the 1702's composite input and I get a beautiful color picture.

 

A while back I had done the same with a modern Samsung big screen TV hooked to my Atari, and I was also get black and white video when using the composite or even the switch box, but when the 1990's TV/VCR combo TV displayed color with the Atari 800 I chalked the problem up to the new Samsung widescreen being ultra picky about its NTSC signal. Now that I see the Commodore monitor doing the same thing with my Atari, I am wondering if the problem is with the Atari?

 

Has anyone used an Atari 800 and a 1702? Could something be wrong with the video circuitry on my 800? Any pointers are really appreciated!

 

Regards,

Adam

[Roydea6]

 

 

try all color end of the 5 din to rca plugs into the Audeo port until you isolate the audio part of the cable..

try the next colored rca plug into luma until you get a picture.

try the next colored rca plug into chroma until you get a colored picture.

 

Make sure the switch is switched to rear ports.

 

if you get audio and still black screen then swap the luma and chroma ends.

 

[+HatNJ]

Plug the same connections u used for the tv/vcr combo you got the good picture on and connect to front of 1702

make sure switch is set to FRONT you should get color if that worked on the combo setup

[gamer-stu]

I agree with rdea6. You're going to have to plug and play. For what it's worth, my cable has the white lead going in to luma, yellow going in to chroma, black in to audio, and red completely unhooked. If you want a more scientific method, use your multimeter continuity function to identify which pin of the cable jack goes to which lead. You can then compare that to the pinout of the 800 monitor port.

[polyex]

Plug the same connections u used for the tv/vcr combo you got the good picture on and connect to front of 1702

make sure switch is set to FRONT you should get color if that worked on the combo setup

Yes,I did. The composite connection that worked fine on the TV/VCR combo TV displays black and white on the 1702 when plugged into the front.

[+HatNJ]

wow thats weird and if it works great with the TV combo and the DVD works on the 1702 good

I wish I could be more help

[polyex]

wow thats weird and if it works great with the TV combo and the DVD works on the 1702 good

I wish I could be more help

 

I know , I can only think the signal on the Atari is weak or strange in some way?!? , and the TV combo is ok with it, while the 1702 (and the Samsung TV for that matter) are not.

[ryanmercer]

Audio is white, luminace is yellow, chroma is red

 

 

On the front your knobs should be tint - color - bright - contrast - horizontal - vertical - hold - volume.

 

 

Have you tried fiddling with the color knob? I'm not at home so I can't check any of my 1702's but I'm not sure you can turn color off with the knob like you could on most televisions back then but it's worth a shot.

[polyex]

Yeah, I have tried adjusting the color knobs. I plugged an Apple IIe into it just now for laughs, color is good. Just getting black and white on when using the Atari 800. Checked continuity on the cable, everything is fine with the cable.

 

Audio is white, luminace is yellow, chroma is red.3

 

 

On the front your knobs should be tint - color - bright - contrast - horizontal - vertical - hold - volume.

 

 

Have you tried fiddling with the color knob? I'm not at home so I can't check any of my 1702's but I'm not sure you can turn color off with the knob like you could on most televisions back then but it's worth a shot.

Edited February 25, 2015 by polyex

[ryanmercer]

Hmmmm.

 

I caguely remember having this problem last summer with an 800xl. IIRC it was the cable.

[ryanmercer]

Noooo I remember what it was. One of my 1702's I bought last summer just won't show color for whatever reason (for my main 800xl, haven't tried the others or any of my 2600's, it displayed color for an NES fine though) and I never bothered to figure out why as I use a Sony PVM to play on and just have my collection of 1702's for the vintage factor.

[polyex]

Noooo I remember what it was. One of my 1702's I bought last summer just won't show color for whatever reason (for my main 800xl, haven't tried the others or any of my 2600's, it displayed color for an NES fine though) and I never bothered to figure out why as I use a Sony PVM to play on and just have my collection of 1702's for the vintage factor.

 

Had you ever seen color with an Atari 800 and one of your 1702's? This may be the problem.

[polyex]

I agree with rdea6. You're going to have to plug and play. For what it's worth, my cable has the white lead going in to luma, yellow going in to chroma, black in to audio, and red completely unhooked. If you want a more scientific method, use your multimeter continuity function to identify which pin of the cable jack goes to which lead. You can then compare that to the pinout of the 800 monitor port.

I did, pins check out OK.

[ryanmercer]

 

Had you ever seen color with an Atari 800 and one of your 1702's? This may be the problem.

 

I don't have any 800's, but I have several 800xl's. I have three 1702 monitors, two of them do color fine on both front and back, the third for whatever reason would only show black & white but I wasn't too worried about it at the time and just set it aside without ever figuring out why it was doing that.

[atari8warez]

Is your 1702 NTSC?

[polyex]

Is your 1702 NTSC?

Yes, I tried it with an NTSC DVD player and got a great picture

[atari8warez]

Some DVD/Blueray players may be able to switch to/from NTSC/PAL, try another NTSC video source other than a DVD player (a camcorder for example)

Edited February 25, 2015 by atari8warez

[russg]

Yes,I did. The composite connection that worked fine on the TV/VCR combo TV displays black and white on the 1702 when plugged into the front.

Plugged into which jack on the front? My 1902, I have a chroma/lumina port in the back. I can get a blue/white memo pad with the 5 pin

jack in the back and the yellow and red RCA plugs. If you don't get a blue memo pad using the composite (black) plug and the

composite port of the 1702, something is wrong with your monitor cable or 800 video. I guess you don't have a second A8 to test the

blue with. I can't get separate chroma lumina with a 600 XL in the five pin port on the back, just get color with the composite in.

I get a black and white with the 600XL in the five pin jack.

Edited February 25, 2015 by russg

[polyex]

Plugged into which jack on the front? My 1902, I have a chroma/lumina port in the back. I can get a blue/white memo pad with the 5 pin

jack in the back and the yellow and red RCA plugs. If you don't get a blue memo pad using the composite (black) plug and the

composite port of the 1702, something is wrong with your monitor cable or 800 video. I guess you don't have a second A8 to test the

blue with. I can't get separate chroma lumina with a 600 XL in the five pin port on the back, just get color with the composite in.

I get a black and white with the 600XL in the five pin jack.

It's composite video on the front with the 1702. Chroma /Lumina on the back. Either produces a black and white picture. The strange thing is I get blue/white memo pad using the TV/VCR combo tv set, but as I said, perhaps the color signal that the 800 is outputting is below some threshold that the 1702 is ignoring , but the TV/VCR combo is ok with? Anyone heard of an Atari 800 degrading to black and white output?

Edited February 25, 2015 by polyex

[adam242]

Have you tried connecting a different source to the chroma/luma inputs? That would narrow down your troubleshooting.

 

Can you provide a link to the eBay listing for the cable?

 

I suspect you have a defective cable, or the wrong plugs are in the wrong jacks. You can try checking with a multimeter as gamer-stu suggested to match the plugs with their function. Here's a link to a pinout of the monitor port. Remember, this is the jack, not your cable's plug, so the pin numbering is mirror-image. I would double, triple check the composite chroma (pin 5). This is the pin immediately left of center, looking into the plug.

 

Good luck - the 800 should provide a brilliant sharp picture when connected this way to a 1702. This is the setup I use every day.

 

 

[polyex]

Have you tried connecting a different source to the chroma/luma inputs? That would narrow down your troubleshooting.

 

Can you provide a link to the eBay listing for the cable?

 

I suspect you have a defective cable, or the wrong plugs are in the wrong jacks. You can try checking with a multimeter as gamer-stu suggested to match the plugs with their function. Here's a link to a pinout of the monitor port. Remember, this is the jack, not your cable's plug, so the pin numbering is mirror-image. I would double, triple check the composite chroma (pin 5). This is the pin immediately left of center, looking into the plug.

 

Good luck - the 800 should provide a brilliant sharp picture when connected this way to a 1702. This is the setup I use every day.

 

 

No, I don't have anything else to check check the 1702's chroma/luna ports. I checked the pinouts on the cable and they are a mirror match to to the diagram and have continuity. The eBay cable is at http://www.ebay.com/itm/-/130888382784

 

The cable also provided composite, which is black and white on the 1702 (color on the DVD/VCR combo TV).

Edited February 26, 2015 by polyex

[russg]

It's composite video on the front with the 1702. Chroma /Lumina on the back. Either produces a black and white picture. The strange thing is I get blue/white memo pad using the TV/VCR combo tv set, but as I said, perhaps the color signal that the 800 is outputting is below some threshold that the 1702 is ignoring , but the TV/VCR combo is ok with? Anyone heard of an Atari 800 degrading to black and white output?

You've checked everything. The 800 does color on TV composite, so your cable and 800 seem OK. The 1702 does color with VCR, so the 1702 seems OK.

I certainly don't know. I made an adapter to plug into the six pin jack on the back. din to RCA. That's about the only other thing I can think of, try the yellow lumina

and red chroma in the six pin jack in the back. Someone else says they use the 1702 chrom/lun, so they have such an adapter, maybe they can tell you where

to get one. Mine is not very nice looking, just an eight RCA board with pins to solder to.

And I somehow soldered wires into the six pin din plug.

Edited February 26, 2015 by russg

[polyex]

I am also getting quite a bit of buzzing in the audio. The buzzing is coming from the audio output. Checked two different power supplies for the Atari 800, same buzzing through the audio channel. Unplug the audio and no buzzing, so the sound is not coming from anywhere else. The buzzing is more pronounced when you are in certain video modes like the menu screen of the SIOS2SD. I am starting to fear something is fried in the Atari 800 to cause the video output to be degraded in some way, and the TV/VCR combo is just more forgiving about its signal quality than the 1702. Is this possible? I have fixed some arcade boards/monitors with bad capacitors, but I am not an electrical engineer. What should I check INSIDE the Atari?

Edited February 26, 2015 by polyex

[MrMartian]

I am also getting quite a bit of buzzing in the audio. The buzzing is coming from the audio output. Checked two different power supplies for the Atari 800, same buzzing through the audio channel. Unplug the audio and no buzzing, so the sound is not coming from anywhere else. The buzzing is more pronounced when you are in certain video modes like the menu screen of the SIOS2SD. I am starting to fear something is fried in the Atari 800 to cause the video output to be degraded in some way, and the TV/VCR combo is just more forgiving about its signal quality than the 1702. Is this possible? I have fixed some arcade boards/monitors with bad capacitors, but I am not an electrical engineer. What should I check INSIDE the Atari?

 

This sounds to me like you have a video cable plugged into an audio jack...

[fujidude]

No, I don't have anything else to check check the 1702's chroma/luna ports. I checked the pinouts on the cable and they are a mirror match to to the diagram and have continuity. The eBay cable is at http://www.ebay.com/itm/-/130888382784

 

The cable also provided composite, which is black and white on the 1702 (color on the DVD/VCR combo TV).

 

When you say there was continuity, does that mean you determined that with a meter? In addition to checking for continuty between the RCA centers and the correct spot on the DIN plug, you might also try checking if there is continuity anywhere where it shouldn't be, just for completeness.

 

Also, try to make sure all the RCA outer conductors have contiinuity to Atari's pin 2 (ground). A lot of time a practice with DIN type plugs is to use the perimeter metal as ground. Perhaps the Atari ties pin 2 to that as well, or maybe not. But one way or the other, each of the RCA plugs need to get their outer conductors connected to Atari pin 2.

 

Here is another graphics based diagram of the Atari8 monitor port pinout for reference.