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About JDW

  • Birthday 02/25/1971

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  • Location
    Aichi-ken, Japan
  • Interests
    Church, family, travel around Japan, Mac computing, graphic design, web design, photography, videography, Newton 2100 PDA, System 6 fun on an SE/30

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  1. Thank you for your experienced input. I certainly appreciate that. That JAMECO web page you linked to is exactly the one I mention in my previous two posts. That chip is show in the JAMECO/Siemens datasheet as this: The above looks pin-compatible with the Micron MT4264 (which I linked in my previous 2 posts): The pin-out markings look to be the same on both the JAMECO chip and the stock MT4264. Are you saying the MT4264 is not the stock chip? Or are you saying the JAMECO chip physically will not fit into the holes due to the pin spacing being different?
  2. No replies after 24 hours indicates an "I don't know" scenario, so I decided to search the forum for an hour and found this 2016 comment by Uniserver. It was his personal opinion that all the Apple logo RAM chips were just waiting to die and he didn't feel that selective replacement was a good idea, opting instead to replace them all. Yet later in that thread I see one person who placed one chip successfully. Whether that Mac is still running now in 2020 is unknown though. It also isn't clear what the speed of the original 128K chips was. Some people say 200ns and others 150ns. The JAMECO RAM chips are mentioned as being 150ns, which indicates they must be the Siemens HYB 4164-2 chips mentioned in the datasheet they provide. But if we compare the A.C. Characteristics on page 6-16 of that Siemens Datasheet to the same A.C Characteristics on page 1-4 of the Micron MT4264 datasheet, we see speed differences even between the 150ns chips... (The Micron MT4264 (-15 or -20) were the stock chips used by Apple in the 128K motherboards.) I am going to guess that the speed differences between the HYB 4164-2 & MT4264-15 are "within tolerance" of whatever the Apple 128K motherboard requires, but if anyone knows for a fact, please chime in. (While it would seem prudent to just swap out all the stock RAM chips for JAMECO's 256x1 DRAM chips so as to get a 512K motherboard, such would also require the addition of a multiplexer. Such is a non-trivial mod.) My biggest problem at this point is that I do NOT have a Hot Air rework station. I merely have a standard Desoldering Station. Chip removal for multilayered motherboards like these are likely problematic at best for a regular desoldering station, and I would assume that a hot air station is really best to avoid problems on these RAM chips. Have any of you been able to accomplish the job with a regular desoldering station? (Soldering in new chips is easy. I am talking about the desoldering and removal of the bad chips.) Thanks.
  3. JDW

    Daystar Universal PowerCache P33 in SE/30

    Did you also run before/after Speedometer 3.06 and/or Speedometer 4.x scores too? I get the same before/after-jumper scores in both of those. NOTE: I have the older model GREEN colored TS Adapter, but that shouldn't matter. I added the jumper across the correct 2 pins. I tried two different SCSI hard drives, but the results are the same. When I run MacBench 3.0 under System 7.1, I get a 4.79 for the Processor score and 1.0 for Floating Point and 20.52 for Disk Mix, which are quite similar to your scores "w/jumper." I didn't have older MacBench 3.0 scores using with the Turbo040 saved though, and I didn't want to desolder the jumper to run the tests again. I also ran Norton System Info under System 7.1 and my scores today were pretty much on par with past scores. I always load QuadControl, so I don't know if that has anything to do with my scores remaining consistent. My 40MHz Turbo040 has the newest 4.11 ROM. (This is the same card @Bolle kindly repaired for me by swapping out the bad Daystar chip.) Now here's the interesting part... I booted into 7.6.1 so I could run MacBench 4.0 (I clicked "Continue" when it complained about the lack of a 640x480 display), and I found differences with past results: Processor w/jumper: 36 Processor without: 28 Floating Point w/jumper: 14 Floating Point without: 12 Disk w/jumper: 113 Disk without: 93 Those differences seem large enough that it doesn't seem like a normal variation that would appear when you run benchmarks multiple times.
  4. A viewer of my YouTube channel recently asked me about a Sad Mac Error code that he is seeing on his Macintosh 128K: 047A80 It would seem to be RAM related as per this: To identify the individual bad chips, we use this... Unless I am in error, the 7A80 part would seem to indicate 6 bad chips at the following locations: 1000+2000+4000=7000, so: G9, G10 & G11 0800+0200=0A00, so: G6 & G8 0080 = F12 Strangely, Mouser doesn't have replacement chips but JAMECO does. As you can see on that page they are $2.25 each (+ shipping). The JAMECO datasheet seems comparable to the datasheet of Apple's stock chips. Any thoughts on what would 6 RAM chips to go bad? Static discharge?
  5. JDW

    SE/30 Restoration Fun

    I shipped my SE/30 motherboard to @Bolle (in Germany) and in January this year he found it was the VROM. He shipped the repaired board back to me and I can confirm his fix worked. Here's what he told me... Hm, the video ROM on your board definitely has flipped bits: On the left is a valid dump, on the right the contents of the chip that came off your board. It looks like whenever there is a difference it's subtracted 4 from the actual value. Looks like there's a bad address input/internal addressing error or a whole cell inside the ROM went bad. Going to replace the one on your board with a spare from my stock.
  6. While testing Zane's 8MB ROM, as I reported to him via PM, my MacCon Ethernet PDS card works just fine with his ROM, even when my MacCon is stacked atop my DiiMO PDS accelerator card. I am able to boot just fine with my 50MHz DiiMO PDS accelerator card (68030) installed, either from a SCSI hard disk or the FloppyEMU (using either a virtual floppy or HD20 mode) or from a real floppy disk. I can format real floppy disks and duplicate disks just fine. The bad news is that the motherboard-socketed Daystar PowerCache 50MHz 68030 accelerator board is NOT compatible with the 8MB ROM, as per the fact it yields the following screen on my SE/30. But on a more positive note, I am able to boot my SE/30 just fine with my DayStar Turbo040 40MHz PDS accelerator card (with TS Adapter) installed (which I cannot do with the ROM-inator II unless I use the OlePigeon patched ROM), but the 8MB ROM only works fine from a SCSI hard disk or FloppyEMU virtual floppy disk (400K or 800K only). HD20 Mode on the FloppyEMU does NOT work with the Turbo040 and Zane's 8MB ROM installed. Also, 1.44MB disks, whether real floppy disks in the internal drive or 1.44MB disk images on the FloppyEMU do NOT work at all, whether I try to boot from them or simply try to mount them on the desktop when booted. If I boot from a SCSI hard disk and insert a 1.44MB floppy, it asks me to initialize it. But again, 400K and 800K disks work fine. If I remove the Turbo040 and TS Adapter, then I can read/write 1.44MB floppy disks again. This seems to be a bug with the 8MB ROM and the Turbo040 for SE/30.
  7. @ZaneKaminski, I sent you some PM's a week ago, giving you a detailed compatibility report regarding the 8MB ROM you kindly shipped to me for testing. I haven't yet received a reply back from you so I thought I'd flag you about my PM's here. Not sure if you are busy or if this forum's email notifications are down again.
  8. EM-30L is hard to find though. It's no where to be found in Japan, and the only seller on Amazon is out of stock. That's why I put an EBAY link to it in the text description under my video on YouTube. SuperLube is much more readily available, and I cover that in my 800K drive video.
  9. I was going to post the video below yesterday, but this forum was down. The topic really doesn't fit perfectly into "Peripherals" because every old Mac has a floppy drive, but I just decided to put it here in hopes this category is the closest fit. Those of you on FaceBook or who are already subscribed no doubt already have seen it. But I am posting it on this forum for others who have not. The video applies to the 800K & 1.44MB drives. I wish to humbly thank @jjclay for buying and shipping me the EM-30L at his expense, without which my video would not have been possible. For those of you who wish to see all 4 of my floppy drive repair and lube videos covering the 400K through the 1.44MB, please note that I have prepared a YouTube Playlist here.
  10. Thank you for the kind words, Eric. Getting the SCSI ID selector to work on my HD20SC has been very useful, so I know you will benefit from the effort required to make it happen on your CD drive.
  11. I just sent you a PM with two videos.
  12. In what Mac? I am trying unsuccessfully to use it in my fully recapped and properly functioning (otherwise) SE/30.
  13. I made a video on the subject here, released today...
  14. Since Zane is not replying, I will ask you folks. I have a ROM sealed inside its anti-static bag. I get only vertical lines on cold boot when used in my fully recapped SE/30 (no PDS card or accelerators attached), even after 3 minutes of waiting. I reseated the ROM, and I even used the metal support bar the ROM-inator II documentation recommends. Nothing works. QUESTION 1: Do these ROMs come programmed or not? It might be blank. QUESTION 2: If the ROM is blank, can I use my ROM-inator II programmer to program Zane's ROM? If so, where is the *.bin file? Thanks.
  15. @ZaneKaminski I've sent you two PMs about your ROM over the past few days but haven't heard back from you. Not sure if the forum notifications are down again, but neither of the YouTube videos I made for you have any views other than my own, which indicates you did not receive my PMs. I don't know your email address, so I cannot contact you that way. Hopefully you will spot this post. Thanks.