Obadiah64 Posted December 7, 2019 Share Posted December 7, 2019 I have a 800XL that is in need of a little work. I was wondering if there was an all in one kit that comes with all major CAPs that would need replacing. Also I was looking to replace all the RAM chips with new ones. I see that it uses the 4164 RAM, but is there anything else I need to be aware of when looking to buy new chips? Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted December 7, 2019 Share Posted December 7, 2019 Don't bother replacing caps unless you have an obvious problem. Atari 8-bits - especially XLs and 400/800 models - were built like tanks. They used excellent-quality capacitors and unless you see one bulging or leaking, there's no need to replace any of them. As for DRAM chips, eBay is your best bet. Quote Link to comment Share on other sites More sharing options...
Obadiah64 Posted December 7, 2019 Author Share Posted December 7, 2019 Sounds reasonable. I do not see any caps that look problematic so I will leave them be. As for as the ram, I did locate some on ebay that are priced reasonably. I think I will get those just to have them on hand. Now the problem that I was experiencing was that the 800xl had no video or sound. Just the power light coming on. So I'm not sure if it was actually booting up or not. But in the last hour, I went back to give the unit a once over again and found a solder point had come loose. We have just moved into a new house, so my soldering iron and such is still packed up. I will get that unpacked in the morning and see if I can get this baby up and running again. Quote Link to comment Share on other sites More sharing options...
Jinroh Posted December 7, 2019 Share Posted December 7, 2019 Best of luck! Interesting finding! I hope you can get your soldering iron out soon. I have not had a chance to open mine up yet, but I have an 800XL that has a similar problem. No BASIC at Boot, just a black screen. However if I put a cartridge in, like Donkey Kong or Pole Position, it runs fine. I will open it now, maybe a loose solder joint as well, or a bad BASIC ROM. Quote Link to comment Share on other sites More sharing options...
xrbrevin Posted December 7, 2019 Share Posted December 7, 2019 avoid using MT (Micron Technologies) RAM chips as they are not robust. Its more rare to find ones that do work! 41256 chips are also a drop-in replacement but the Atari will only use 64k 1 Quote Link to comment Share on other sites More sharing options...
Obadiah64 Posted December 7, 2019 Author Share Posted December 7, 2019 Well, I was able to get the solder joint re-soldered. Unfortunately that was not the problem. It will power on as for as the power light coming on and the monitor does seem to detect a signal, but no video or sound. Is it possible that it is a memory chip that is the culprit? Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted December 7, 2019 Share Posted December 7, 2019 10 minutes ago, Obadiah64 said: Well, I was able to get the solder joint re-soldered. Unfortunately that was not the problem. It will power on as for as the power light coming on and the monitor does seem to detect a signal, but no video or sound. How are you connected and what kind of display are you using? Do you have any cartridges to try? And please post a photo of what PSU you are using - there is one common XL/XE power supply that is a ticking time bomb and has killed numerous machines. 1 Quote Link to comment Share on other sites More sharing options...
Justin Payne Posted December 7, 2019 Share Posted December 7, 2019 I've just completed a list of electrolytic caps if you're interested. I haven't put a list of links to replacements yes. I usually go up on the voltage a little just because it gives a little more headroom. For example, 10(16). The original cap is 10v but I'd probably get a 16v if available. When I purchase, I bold the voltage just so I know at a glance what I replaced it. The 800xl has 5 axial caps, which are generally waaaaay more expensive that radial. I'll try to replace like for like but if a radial is < $1 and the axial is several, I'll go with the radial. I'm not rich enough and I have other systems that probably need caps as well. Quote Link to comment Share on other sites More sharing options...
Obadiah64 Posted December 7, 2019 Author Share Posted December 7, 2019 (edited) 5 hours ago, DrVenkman said: How are you connected and what kind of display are you using? Do you have any cartridges to try? And please post a photo of what PSU you are using - there is one common XL/XE power supply that is a ticking time bomb and has killed numerous machines. This is the power supply that I was using when the unit went kaput. Since then I have purchased a power supply from The Brewing Academy. I did try a cartridge (Donkey Kong) with no luck. Edited December 7, 2019 by Obadiah64 Extra Info Quote Link to comment Share on other sites More sharing options...
Sugarland Posted December 7, 2019 Share Posted December 7, 2019 Uh oh! That is the machine-killer ingot! It could be just one component/chip is bad or several. I'm not sure but I think leaving it powered on for 5 or 10 minutes to see if any chip gets really hot, especially the RAM. GTIA is normally very warm however with the CPU in second place. Do you have a voltage meter? Testing the ingot's voltage is a good idea (but don't plug it into the 800XL again). Don't throw it away yet. Before you do, save the 5 pin DIN connector + cord by cutting near the PSU. Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted December 8, 2019 Share Posted December 8, 2019 Ugh. Don't use that PSU again. Cut off the DIN jack if you want to salvage the connector, but otherwise toss it in the trash. Your best bet at this point is wait for the new PSU if it hasn't arrived yet. You can resume testing when it arrives. When it does arrive, fixing the unit can take several different paths, depending on your skill, available tools and whether you have access to a socketed working Atari for chip-swapping. Quote Link to comment Share on other sites More sharing options...
Obadiah64 Posted December 8, 2019 Author Share Posted December 8, 2019 Ok I'll ditch the PSU (minus the DIN). I do have a working 800xl w/sockets and the new PSU is here. I guess I'll put some juice to the unit and see anything gets a little too warm. Maybe it will be something obvious. I'll have to try and find my multimeter to do a little testing also. I appreciate the advice guys. Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted December 8, 2019 Share Posted December 8, 2019 1 hour ago, Obadiah64 said: Ok I'll ditch the PSU (minus the DIN). I do have a working 800xl w/sockets and the new PSU is here. I guess I'll put some juice to the unit and see anything gets a little too warm. Maybe it will be something obvious. I'll have to try and find my multimeter to do a little testing also. I appreciate the advice guys. Okay excellent. So, assuming your touch test doesn't find a really hot (like, scorching) chip that's shorted internally, here's the best thing you can try without access to something like a logic probe or an oscilloscope. Try each of the main IC's one at a time and try them in your working 800XL - don't put chips from the working machine into the dead Atari. You risk damaging them if whatever killed the other machine is larger than just a bad power supply - it's not at all likely, but there's always a chance you have some kind dead-short on the board and if you put a known-good chip into the dead machine, you might damage it. Therefore, try the chips from the dead machine in your working 800XL one at a time. With luck you'll ID the bad chip(s) pretty quickly. If swapping ICs doesn't identify the culprit, you're going to have to do some testing with some kind instrumentation. You can check basic voltages and stuff with a multimeter but a logic probe or oscilloscope would give you a lot more info, assuming you know how to use them. It might be easier to find someone relatively close who can look at things for you. Quote Link to comment Share on other sites More sharing options...
Obadiah64 Posted December 8, 2019 Author Share Posted December 8, 2019 (edited) Found a couple of "Scorching Chips", 2 of the RAMs. Was able to replace them with 2 good ones and we are in business! Now I have 2 working 800XL's. Fantastic! My next project is to upgrade one with a ULTIMATE 1MB and a Sophia rev. C (DVI output) Thanks again for every ones input. Edited December 8, 2019 by Obadiah64 Added photo 4 Quote Link to comment Share on other sites More sharing options...
Justin Payne Posted December 8, 2019 Share Posted December 8, 2019 It was requested that I post this list of electrolytic caps for the 800xl. https://docs.google.com/spreadsheets/d/1Cus0X3U_EiTk8svkk5F-cPMIGge1szRvq_MaVmU_rlQ/edit?usp=sharing 1 Quote Link to comment Share on other sites More sharing options...
Obadiah64 Posted December 8, 2019 Author Share Posted December 8, 2019 2 minutes ago, Justin Payne said: It was requested that I post this list of electrolytic caps for the 800xl. https://docs.google.com/spreadsheets/d/1Cus0X3U_EiTk8svkk5F-cPMIGge1szRvq_MaVmU_rlQ/edit?usp=sharing Thanks. Much appreciated. 1 Quote Link to comment Share on other sites More sharing options...
Justin Payne Posted December 8, 2019 Share Posted December 8, 2019 Lead spacing might be wrong on those axials. That is the spacing on the board itself. On Mouser, the axial caps are wider. The originals are about 4mm where the ones I found on Mouser were about 6.3mm. In most cases they look like they will fit except for one cap where it might be a bit tight OR will have to raise it up a bit on the board to clear another component. As mentioned you in my PM, I haven't decided on getting the axials due to the width and the price. It might be worth replacing those with radials. Of course, if you're thinking about adding upgrades, such as something from Lotharek, clearance might be a consideration and those axial/radial replacement might pose a new problem. I'm going to hope to get some of those Lotharek upgrades for Xmas so I'll have a better idea at that time. Quote Link to comment Share on other sites More sharing options...
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