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Bikerbob

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About Bikerbob

  • Rank
    Dragonstomper
  • Birthday 11/25/1968

Profile Information

  • Gender
    Male
  • Location
    Mississauga ON Canada
  • Interests
    Sailing, Computers, Motorcycles

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  1. YES, , one thing I would say and agree.. try and keep all 8 the same.. trying to mix chips does not mean they are bad, but might not work together.. my experience in this thread. To those that were following.. 8 new ram chips in.. machine is good.. mmu was not an issue. James
  2. No the MT branded ram.. only one chip was bad in that machine. its Mostek 4564-15.. All the personality chips are fine in the machine.. nothing else got hot. James
  3. Hello all, I fixed my one 800xl for my friend - only 1 bad ram chip - lucky! The other one the ram was heating up.. I tested the chips one by one in a known good working machine.. EACH ONE Failed to boot it. Have you seen all 8 ram go bad without something else causing it? I am afraid to put new ram in... James
  4. oscilloscope is really big on my list DrVenkman. I have run into so many times where I could use it. now that I am doing more repairs for people. James
  5. So the MT ram.. is soldered on.. I guess the only way to determine if its good or not it to remove it. and put sockets in. I will see if the owner wants to do that. The ram that is in the HK board.. this is the one with the factory "mod" of the resistor and the bottom pic with the drill holes breaking the original trace.. I will check that for missing or cold, etc.. Both machines do trigger a signal to the TV.. though black screen.. I use IPA .. do people find this Deoxit better?? Thanks James
  6. Going to add to this thread, because it is a same type issue. I have a good HK socketed 800xl that I use to test others. I am trying to fix a couple of 800xls for friends one is a Taiwan solded board and the other seems like a very early HK revision C as you can see by the picture the ram sockets were dont this way to accommodate the factory mod. So both the HK rev C and the revD Taiwan I have black screen. The HK rec C was Super hot ram.. and when I put them 1 by 1 in the HK tester.. it failed to boot.. but 8 bad ram??? Notice the HK tester does not have the resistors on the ram. The Taiwan board ram is cool, I have swapped IC chips.. no change.. any suggestions?? James
  7. where do you find the games if you would like to try them out?? no matter what I click I go to facebook pages for ZeroPage.. nothing about the games themselves???? James
  8. David did you do Global express? Does this mean Global express for the price of Post office.. aka $10 off! James
  9. Well I just picked up a CTIA 800 .. so there ya go.. Poke 623,64 - nada.. (I also opened it when cleaning and saw the part number ) James
  10. Sent a PM.. would like 1 possibly more if any still available. In Canada.
  11. c012295 ctia in it... just read that CTIA shipped until 81.. so could still be 81.. weird I thought CTIA was gone long before.. James
  12. How about this?? complete matching numbers. Where does this put me, date wise?? I get the 16 of 81.. but I have never seen a number so small. Did anyone ever figure out what the letter codes me? whats G or AW or in this one WW??? very early rom /* OS rev. A (1979) from early NTSC 400/800. Part no. C012499A + C014599A + C012399B */
  13. I think I have everything working again John.. I have put it away, and I dont remember any issues when it was put away.. I have been dealing with my STs.. selling and re-arranging.. I have not done any hardware bbs stuff since.. I will get back to it though!! Have to get my bbs up and running.. I hope Starfeet gets back up.. I miss it. James
  14. 3mm led on a 24" length of twisted wire.. to a 2 pin female header. Plugs in right behind the RTC battery. J290 positive to the left. James
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