Jump to content


New Members
  • Content Count

  • Joined

  • Last visited

Community Reputation

3 Neutral

About 7bits

  • Rank
    Space Invader

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. Thanks, guess I was too slow!
  2. Sorry, thought I would get notifications. I am in North America but will pay to ship from wherever. Also I dont care if it is NA spec or UK spec systems.
  3. I have tracked down an STE, on to a falcon and TT! Thanks all!
  4. The internuts has said, that its the filtering of light via the windows that causes the yellowing, if you have direct sunlight with windows with UV coatings, you can have problems. The other issue I suppose is temperature, I know for a fact, I have had keyboards in storage in a sealed box, with no light I have taken out years later and they turned yellow. These were in my basement, so other than heat in the summer and freezing in the winter, not sure what caused that. I have also experiment with direct sunlight on Famicoms and 1050 drives, amiga keyboards, etc they all lost a vast amount of the yellow, but not 100%. There is risk of course of making the plastic brittle from heat, but that is why even now in the cooler weather, this works with nice bright sun like we had in New England today.
  5. Well if it makes you feel any better, I leave mine away from the windows, but they for sure are not covered up, just no direct sun.
  6. US or UK versions are fine. I won't lowball either, as long as it is a good clean unmolested system I will pay top dollar.
  7. I can imaging if this came out back in the day what an amazing achievment.
  8. Am I being paranoid thinking about all the sun and heat will yellow some of those systems over time?
  9. For me it ended up being the side board. Even though I swapped every socketed chip, and the daughter board, it wouldn't work with that board.... I can't remember if I had trouble finding good schematics. I checked voltages everywhere and seemed good so I assumed at this point I have a bad discrete component somewhere, looking over all the solder joints, traces nothing wrong. The weird thing is this does seem to be a common error state. Life got busy, so I already forgot what I did, I think I gave up and swapped the guts from an 810 that has everything working as there are plenty of 810s with smashed cases, that 70s plastic is brittle!
  10. Seems like an appropriate thread to continue. Is it normal for the CPU to get so hot to the touch, it feels like it will burn you? I would think not, but what temperature do people think is normal?
  11. Yes, I got some spare supposedly working sideboard/data seperator boards but then I think I fried something trying to narrow it down LOL. It booted once, than that was it... Unless the head burned out. So last place I was at, was I was able to boot off the 810 once, then went to test the data separator board, I think it worked. I swapped the smaller ICs at Z101 and Z104 from my bad side board into the good one. Then it didn't work so was ah ha!, so swapped it back, then didn't work. Thats what I get for trying to narrow down the chips So at this point I can boot off a 1050, and initiate a format on the 810, it does the chunk chunk chunk, gets to the last track on in inner hub and sits there till it times out, this is doing a single density format on the 810. The disk I try to format is a single density disk that is already formatted with DOS 2.5. Still works after the ghost format. Other drives I can test the coils for the erase and read heads if I know the pinouts. Any advice on that? I guess thinking now I can check the service manual.
  12. Narrowed it down to the side board. Data separator board is good.
  13. I also looked up the stepper motor, its a Minebea Co Stepper Motor 17PS-C006-01. Since it was five wires, I did the ohms test to find the + wire between each one, taking the lowest ohm reading. In this case I started with the black wire and each wire paired to that had equal ohms, so that means the black wire is the positive wire. Then ran 12 volts to the black wire on the stepper motor from my bench PSU and was able to cycle each of the 4 stepper wires and move the drive head from back to front and then cycle it backwards to track zero. This convinces me the stepper motor is not shorted/works OK and not feeding anything back to the side board. So back to the side board and waiting on SRAM. Other than the cracked joints on the power regulators, all connections look good. May crack out the oscilloscope next. I love a puzzle If the SRAM doesn't fix it I will be looking closer for some bad transistors. I suspect still that the stepper motor transistors may be bad, the ones that sit between the RIOT and some diodes/stepper motor.
  14. Yep. But I figure at this point, 3 bad ones(1 Original and 2x NOS ones) ? Maybe not. Or the NOS ones I got were bad ones stored back in a package. Pretty sure they were new as they both had Pin Spread so to speak. I just threw it in the Music cart, did EXACTLY the same thing as when I put the 810 ROM in the Basic socket in the 800 XL!
  • Create New...