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Dropcheck

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Dropcheck last won the day on June 6 2023

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  1. My overall goal is to redesign for a 1200XL case, since those cases are way more common than a 14xx case. I wish I could mod cases as well as some here on the site. It would take some planning to do it a 1200XL PBI mod right(to provide adequate spacing for attachments etcs), but not that hard. I have plenty of proof that's not one of my strong suites.
  2. Just an update: About 70% done with mainboard assembly. Found a few tweaks I'll have to make in the next version. Primarily spacing revamp and physical part conversions. Axial to Radial on some of the electrolytic caps. Obsolete and not readily available parts is the reason. I'll be cannibalizing one of my 1200 machines next for some parts, mainly connectors. The 1200 was a hanger queen, so had a good life and will live on in the 1450XL
  3. That's good. If the WD1772PH is good, that's half the battle. They are so hard to find nowadays. The jumper setting for the 8040/8050 controversy has cleared up in the last year or two. Normally keep the jumper setting on the 8040 side. The only time you need to move to the other side is if you know the 8050 you have is one preprogrammed by Atari. In that case the source drive would not normally have had an eprom installed. The 8050 has the ability of 4k storage builtin and Atari tried to reduce costs by programming the OS into that storage and eliminating the eprom chip. Not many drives were produced that way, so the chances are slim yours is one of those. The OS jumper is simply to allow you to burn two OS's into one 2764 eprom and then choose which one you want to use. The jumper just selects which bank of the eprom is active. The resistor array should have an indicator for pin one at one end on the lettering side and of course that should go into the only square pin hole(pin 1) on the array footprint on the board. Let me know how the new 8040 goes.
  4. Glad to see some lifeπŸ˜ƒ. I thought about a short later in the circuit, but didn't think very hard or long. Fixated on the problem with input voltage instead. πŸ˜” One thing to keep in mind now is that a multitude of a things maybe going on. Because a multitude of things are going on. Try to get methodical. Write down what you change every time, test. note response, if no go, change it back. Change something else, test, note response, no go, change it back. I tend to get in a hurry and try several things at once. Not good. I quickly lose the thread of what changed and what the results were if any and end up chasing my tail for an hour or two. Do you have a way to check the clock crystal substitute for proper 8.3333MHZ speed? If it's off by too much, the drive will appear to not see the Atari commands. Off just a little and it may read, but can't write stably. The sad state of affairs with chips not sourced from a functioning drive in your possession is that it's very easy to get a bad one. Especially the 1772PH chip. If the replacement 8040 doesn't work then try another SIO cable too, I've had them break internally after years of use.
  5. Substituting parts by a builder is a reality that anyone who has released their designs to the public has to deal with up to a point. If the builder has matched the spec sheet of the original BOM items, it should work. But should and does doesn't always match. That's why I ask him to substitute a bog standard 7805 regulator to see if his substitute was not able to do the job. It apparently did not correct the issue, so something other than the substitution is going on. Substitution by the designer is a reality when parts go obsolete, but simple like for like form substitutions should not affect the function of the design. Mytek's 1088XLD power supply circuit is fairly well tested, so adding the flexibility of a different power switch wired correctly should not affect the function. His 1088XLD uses the same 1050 9VAC power supply as the XF551 original design. The only question might be 50Hz vs 60Hz. I don't remember which the Aussies use, but I am assuming that it works normally on a standard 1050/XF551. Soldering skills are always going to very, but perfection is not required for the board to work. As long as he has reflowed the joints I asked him to and we don't have a parts failure or incorrect orientation, he should be getting correct voltage to the right places. Definitely the parts legs should be clean and rust free. That can cause a problem with voltage transmission. The bodge wire should have corrected the only obvious error in the schematic design and it appears to have been properly installed from what I can see. That is still a weak point, but did restore +12V that wasn't working before. A full +5V is still missing. It would help to only assemble the board in parts, ie power supply first, test to verify correct voltages, then assemble all but track display circuit, test for function. There's not really anything between the first assembly part and the second. The track display circuit is not needed, but everything else is for a functioning board. Trying to troubleshoot remotely is never a fun thing, too many factors you don't control and can't visually check. Or probe. But that is the deal with DIY. I'm willing to help as much as I can.
  6. Sorry missed the line on trying a different power supply. I'm not seeing anything obvious. Let me retrace my steps in design and see if I missed something else. Don't know how, but if I was perfect I would be only 30 years old and living in Utopia. Not here in po-dunk Oklahoma pushing 66. Mouser and Digikey seemed determined to do away with TH parts altogether as fast as they can. Sometimes progress ain't. I noticed that Digikey seems to have discontinued a couple of parts. Mouser still has them for now.
  7. Okay not good. πŸ€• Let's see. Did you reflow all the solder joints on the power supply circuit? Did you check if you are getting both voltages on the drive power cable connector with the power switch off? Shouldn't get either one. Do you have another 1050 power supply to substitute? I suspect that we just don't have enough voltage/current getting to the +5V regulator.
  8. The 800 is the only Atari with a 4 port joystick and a memory mod/OS upgrade called the incognito as far as I know. How that would work with a PBI/1091XL interface I don't know.
  9. You read my mind on source info.
  10. Some things to consider: Motherboard form factor/Casing -- If you want to roll your own then you are going to be chasing whatever form factor the motherboard and its succeeding versions will be. Forever. Not very many customers/users have the ability to 'make' the case themselves and being non-standard will be very costly in most cases(pun intended) to make. You can get as wild as you want, but it's not very cost effective. It doesn't matter what material you use for the case or what manufacturing process you use, unless you are talking about thousands of units at minimum. If you instead fix on a standard PC motherboard form factor, then you have a wealth of different style ready made cases to chose from. The motherboard designer only has to fit a certain set of standards while the user can chose a case style within that form factor to suit themselves. Even here you can get fanciful, but still keep to a reasonable budget. Feature set -- Sometimes less is more. I agree with Mytek, at some point you have to set in stone what is the most likely setup and then design for that. There's not one person here that doesn't have a favorite thing about the Atari 8bits that they would like to have. But somethings conflict with each other and I'd hazard to guess that most options will not be used in the end. Besides I don't know if I want to see such a Frankenstein motherboard anyway. Halloween is still many months away. πŸ˜ƒ
  11. It's the 'but other than that' that he needs to check. I've had a 1050 power brick that looked good, but wouldn't power the drive. Replaced the power brick with another one and it worked. It's a quick and easy check, so it's worth a few minutes time.
  12. One other thing you can try is use another 1050 power supply. These things are going on forty years old now, and while they may have the voltage, they aren't pushing the current they used too.
  13. I doubt it. If you are actually reading voltage at pin 3 of the Traco regulator and it's way below +5V, the inductor isn't even in the picture yet. The circuitry after the regulator mainly conditions the shape of the signal, filtering and smoothing out ripples. You can replace it if you want, but I don't think it will make much difference.
  14. Nice unit. Talk about a heavy laptop for the screen size........ Does it have rollers on the bottom of the case? Does it understand ATX standard or does it only do non-conformist laptop 80's/90's era exceptionalism? πŸ˜€
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