Wow great video. I like that you went step by step testing all the chips. I may need your input for the Atari I am working on. I'll have to see if I can find a schematic and do what you did. I thought I had it, but then thought I smelled something burning so I turned it off and stopped for the time being.
Thanks. I feel bad I didn't record myself scoping that entire chip out and showing what it was doing. I thought I was but when I checked the footage, nope.🤣🤣 But I think y'all understand. If you need some help let me know. What kind of Atari is it, console, computer, handheld, the Atari Video Music (that would be cool)?
I bought a 600XL that was DOA. Fortunately the 600XL was fully socketed and I had several 800XLs that were also, so I swapped chips one at a time to see how they affected the 800XL. I had a bad CPU, a bad PIA, and a bad POKEY. Fortunately, no other major chips failed, but when I swapped all the good chips into the 600XL I still had a blank screen. I had some 4464 chips and on a hunch I jammed them in the computer and it came up and worked. The memory was still only 16K so I took a chance and installed all the jumpers and the computer booted with 64K memory. I ordered new chips from Best Electronics and had the 600XL working fine. Now I just need to figure out better video. I do have a 1090XL replica and an 80 column card, but anything else goes through the RF.
Nice! Glad you got it to work. With all those bad chips, that seems to indicate to me that it was overvoltaged before you bought it. Probably somebody plugged in one of those ingot power supplies that were bad and just fried all the chips.
If the chip is socketed, I'd check that socket. If it isn't the socket, then you would have to check the traces going from the power and ground to that chip to see if they have continuity all the way through. It could be a broken trace. If everything checks out, then it could be a PSU issue. At least that's where I would start with these steps.
I pulled my black screen 600xl apart. They are harder to disassemble than a Commodore pc or even the later ST machines. I found it hard to remove the motherboard from the case and difficult to get back in. THe ports stubbornly do not wish to line up again. Anyway. I tried swapping all the big chips from another 800xl that has memory issues. No change. I noticed the 600xl as many more socketed chips but i do not have spares for them. If i have swapped all the main large chips and no change do you have any ideas? I could just make this a display piece but thats kind of sad. Also the 800xl has a green screen with one line of multicolored character's all in one horizonal line any idea on that? :)
Could be your delay line chip U13 on the 600xl. Those will cause a black screen too. On the 800xl, sounds like an Antic issue, but IDK unless I had it in front of me with a scope, or my chip tester I couldn't tell ya.
@@blackterminal The delay line chip is not being made anymore. You can try best electronics, or they make a kit you can build to replace it on PCB way. www.pcbway.com/project/shareproject/ATARI_600XL_800XL_delay_line_CO60472_replacement_17cb2acf.html, The chip number is CO60472 for the delay line. But I would scope it out to see if you have clock signals coming out of it first.
Wow great video. I like that you went step by step testing all the chips. I may need your input for the Atari I am working on. I'll have to see if I can find a schematic and do what you did. I thought I had it, but then thought I smelled something burning so I turned it off and stopped for the time being.
Thanks. I feel bad I didn't record myself scoping that entire chip out and showing what it was doing. I thought I was but when I checked the footage, nope.🤣🤣 But I think y'all understand. If you need some help let me know. What kind of Atari is it, console, computer, handheld, the Atari Video Music (that would be cool)?
I bought a 600XL that was DOA. Fortunately the 600XL was fully socketed and I had several 800XLs that were also, so I swapped chips one at a time to see how they affected the 800XL. I had a bad CPU, a bad PIA, and a bad POKEY. Fortunately, no other major chips failed, but when I swapped all the good chips into the 600XL I still had a blank screen.
I had some 4464 chips and on a hunch I jammed them in the computer and it came up and worked. The memory was still only 16K so I took a chance and installed all the jumpers and the computer booted with 64K memory. I ordered new chips from Best Electronics and had the 600XL working fine. Now I just need to figure out better video. I do have a 1090XL replica and an 80 column card, but anything else goes through the RF.
Nice! Glad you got it to work. With all those bad chips, that seems to indicate to me that it was overvoltaged before you bought it. Probably somebody plugged in one of those ingot power supplies that were bad and just fried all the chips.
What would you do if a chip shows no ground or voltage?
If the chip is socketed, I'd check that socket. If it isn't the socket, then you would have to check the traces going from the power and ground to that chip to see if they have continuity all the way through. It could be a broken trace. If everything checks out, then it could be a PSU issue. At least that's where I would start with these steps.
I pulled my black screen 600xl apart. They are harder to disassemble than a Commodore pc or even the later ST machines. I found it hard to remove the motherboard from the case and difficult to get back in. THe ports stubbornly do not wish to line up again. Anyway. I tried swapping all the big chips from another 800xl that has memory issues. No change. I noticed the 600xl as many more socketed chips but i do not have spares for them. If i have swapped all the main large chips and no change do you have any ideas? I could just make this a display piece but thats kind of sad. Also the 800xl has a green screen with one line of multicolored character's all in one horizonal line any idea on that? :)
Could be your delay line chip U13 on the 600xl. Those will cause a black screen too. On the 800xl, sounds like an Antic issue, but IDK unless I had it in front of me with a scope, or my chip tester I couldn't tell ya.
@@RetrogamerGenX thank you for the tip! I will see if I can get one of those chips. Do you know the chip number?
@@blackterminal The delay line chip is not being made anymore. You can try best electronics, or they make a kit you can build to replace it on PCB way. www.pcbway.com/project/shareproject/ATARI_600XL_800XL_delay_line_CO60472_replacement_17cb2acf.html, The chip number is CO60472 for the delay line. But I would scope it out to see if you have clock signals coming out of it first.