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About KLund1

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  1. I fond the problem! The was a staple jammed under ram lot 1! The kind of staple from a desk paper stapler. Only about 2mm were visible. It was stuck under, from right to left, pins 11 and 12. It was making contact with the slot pins and a via there. But I mean this was fully jammed under the black plastic. I had to pull hard to get it out. I have no idea how it got in there. But I'll bet that is why this machine was retired back in the day. Well it works great now. Another 800 saved!!! Thanks everyone for the help and advice. Always very much appreciated!
  2. Yes. I have a working exact same Rev A board. Well just tested it and it does not read the Return key. It works fine on the bad slot 2 board Whats your thoughts?
  3. Hi, I got an 800 with odd behavior. It will not boot with any Atari ram in slot 2. I have pulled the whole machine apart and have only the base plane, and power board out and connected. I have done the usual. cleaned the slot and board. Re-seated all the base plane chips, and ram module cards. With only 1 16K ram module in slot 1, it boots. I put in a SS2.07 cart in and tested all 3 16k ram modules. They all pass. I have switch all 3 16k to all positions and no change, it will not boot with anything in slot 2. They all boot in slot 1. I have swapped out the OS and CPU boards with several other known goods one I have on hand. No difference. Well, no, sometimes I get a yellow full screen, or a full black screen. I have reflowed the slot 2 joints. no change. I tested the LS chips in a little tester I have they all show as good. I put some Deoxit in the slot, no change. I looked for any physical damage with a 10x glass but saw nothing alarming. I put a Practical Peripherals MM1632 ram card set for 16K in slot 2 and it booted, but only shows in SS2.07 as 24K. So it looks like a 8K card. Oh, all testing done with a 16K in slot one, of coarse. I often swapped slot 1 ram with another 16K just to make sure it was not that card. Any ideas why it is doing this? Possibles fixes?
  4. Still looking for a little help finding this correct part. I am unsure how to select one of these on Digi-Key? Anyone?
  5. Hi all! I have a MST2 that boots normally. But is has black vertical lines on screen. The are 2 pixels wide on low Res, and are about 1/2" apart from eachother all the way across the screen. I have done Ram and chips tests from the the 4.4 diagnostics cart, and YARRT tests, and all pass with no errors. (the vertical lines are present during all this too) When in Gem, everything appears to work normally, disk access, read, format, play a game. Sound is fine. There are original Atari made 2 chip TOS 1.2 ntcs rom. I tested with another monitor and get then same thing. I have pulled and reinserted all socketed chips. No change. I have swapped the Shifter and DMA chips from working MST2, no change. I have reflowed Shifter and DMA sockets, and any other near by that could be a bad joints. No change. Suggestions, Ideas? Thanks !
  6. About 15 years there was a run at Best Electronics for all the leftover empty 1400 and 1450 boards. I'd guess about 50. Some people tried to populate them. I have not seen or heard of any successes. One of them may be willing to scan one to help make a reproduction. Note there are 2 versions of the 1450 board. One same size as 1400 but needed a daughter card for the floppy drivers. And large Tong board with floppy interface built in and it will not fit in a 1200/1400 case. I think there are schematics out there for all three if you want to design your own board. Possibly optimizing them for size and more easily avaliable parts and eprom usage.
  7. Understood. Many thanks for the quality advice. Will order same value parts.
  8. Tested Cap in the "hot" area with my incircut DCR tester. and bad news C41, C99 and the big one C39 all read low. And of course I do not have any new of that size. I use a standard rebuilt Atari PSU with near perfect output. Now adding to my DIgiKey shopping list. C41 & C99 are 22uf 16v. Is there a better uf and voltage that would be better there. The C39 is 10,000uf 16V are there better values for this too? Thanks
  9. Thanks thanks. The 800XL was a 3 point connection not 4. Very much appropriate the kind offer. This community is always helpful. Any know the right part to buy. Again thanks
  10. I have a similar problem with this 800xl color potentiometer. The unit I'm trying to bring back to life has lost the top plastic part. It does not make good contact between the halves. It needs replacement. Easy fix if I have the right part. Could one of you parts guru's point me to the correct part on digi-key, please. I think it is a 500K, at least that is printed on another 800xl I have. (an aside, I looked at the Best Catalog, and did not see any potentiometers listed. Guess he does not have everything in that book.)
  11. I think it was just sitting the FujiNet main screen. It was probably sitting a good 4+ hours idle with I got back and noticed it. (a/c room 75', not in sunlight) More testing with various setups and it get very warm with my SpartaDOS X Super Cart running. Just looking at disks dir's and some disk formatting on a USD 1050. Oh, moved a few files. Nothing major. It is less hot with other carts, games. Warms up more with use, loading files from internet, or coping from internet to SD. Does get hot with "printing" a long Basic listing, but that would seem normal as the radio is in heavy use. But it is very hot. I would not want to touch the heat sink! The outside cart and case were quite hot. I bring this up as I am going to show it this weekend at VCF-W. It will be on probably 8 hours straight, 2 days. I will put a small fan on it just to be cautious.
  12. I found another Action! Cart. This is a black 1 eprom cart. ?$B8000 shows 32768, $B8000 = (heart) $0000 0 0 Attached a rom dump of it. Hope this help too. Action! Black Cart (mbm27128).BIN
  13. I have been using FujiNet a lot these past few days. Learning how to use it. Wonderful device! After a couple hours, I have noticed the FujiNet, and just the right on the unit at the rear of my 1200XL, it gets VERY Hot. I'd guess about 110'-120'f. You do not want to leave your hand there. I do not have a fancy remote thermometer to get an accurate number. I have tested this a bit further and it is about the same while in use with wifi, and idle and connected to wifi. I noticed this after I had let the system stay on when I went to run some errands. When I came back there was lots of noise on the left side of the attract screen. Attract worked changing colors. but the otherwise the system was locked up. I went to press the fujinet reset button and noticed the heat! lots of it. After I let both cool, and restarted they were working normally. Then I monitored the temps as noted above. Before I noticed the heat, I had upgraded from ver 1.3x to 1.5x. Is this normal? What more info is needed to be helpful
  14. Yes I have seen your site. I did not make the mental connection, sorry. You helped me with designing some Diagnostics cart labels a year ago. Great to see you on our club SLCC Zoom call a few weeks ago. Hope you can attend again when you have the time.
  15. I seem to have misplaced my instructions/manual for this cart. I searched in here but the terms are a bit too general to find it. Can a kind soul point me in the right direction please? Thanks
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