Recent content by jdmcs

  1. jdmcs

    Has Anyone Put a Color LCD Into an IBM 5155 Portable Personal Computer?

    I've seen the LCD panel upgrade available for the Macintosh SE/30, and got a crazy idea: put an LCD panel into an IBM 5155 and connect it to the internal composite output on the IBM CGA card. Or maybe the internal composite output on an ATI EGA card. Or, worst comes to worst, the VGA output on...
  2. jdmcs

    Putting a 486dx in an Intel overdrive slot

    The motherboard likely needs to have jumper settings changed for a DX2-66 processor to work. If you post a photo of the whole motherboard, we might be able to help figure out which one it is. And if a site like The Retro Web has the motherboard listed, we might even be able to help with which...
  3. jdmcs

    Can You Put a White Phosphor CRT into an IBM 5155 (Portable Personal PC)?

    I'm glad I found an amber CRT for my 5155 by means of a parts 5155: while the white phosphor CRT should work, it would likely encounter the same challenges as putting the amber CRT into a Mac. However, there's always the matter of that parts 5155, if I solve the case challenges (it looks like...
  4. jdmcs

    Swap Meet Near Dulles, VA on August 24: Retro Bits and Bytes Swap Meet

    It is a swap meet, so presumably you would be allowed to bring an iBook to “swap”… that’s my guess, at least, I only posted this event for additional exposure (I’m one of the vendors.)
  5. jdmcs

    Swap Meet Near Dulles, VA on August 24: Retro Bits and Bytes Swap Meet

    On August 24, 2025, the Retro Bits and Bytes Indoors Swap Meet will be held at the Dulles South Recreation and Community Center from 1:30-6PM. General Admission is $5 and includes a beverage and a raffle ticket for a SONY VIAO vintage computer. Kids under 10 are free. (I will be attending as a...
  6. jdmcs

    Documentation for DB15 to VGA adapters

    I just found switch settings for the Belkin F3H1381... both versions. Hopefully this helps someone with this adapter, especially because some places have only one of the two manuals. One version of the Belkin F3H1381 does not have a rotary knob, and this version is configured as follows...
  7. jdmcs

    LC II vs. 4MB SIMM Problem

    I’ve been told that the 10MB limit is in the ASIC itself, which would mean that it would not be possible to overcome the limit with an extension. There was a PDS accelerator card that allowed more than 10MB of RAM, but that extra RAM was on the PDS card, allowing it to bypass the ASIC on the...
  8. jdmcs

    LC II vs. 4MB SIMM Problem

    The LC II is compatible with standard 30-pin SIMMs that are rated 100ns or faster (-10 or smaller for the timing). The LC II doesn’t do parity, but the extra chip shouldn’t be an issue. I always suspect memory first: Try running Snooper 2 (not the Emergency Disk version) after booting with...
  9. jdmcs

    Apple IIe Platinum not Detecting Disks

    I usually use this book (Apple II Plus/IIe Troubleshooting & Repair Guide) as a starting point in troubleshooting. Given how throughly you've gone through the system reseating items, you might have a component failure.
  10. jdmcs

    How to: Build an External Power Supply for Atari 520ST (Using Parts from Amazon US)

    DOS Fox told me that the Cisco 34-0874-01 power brick is another candidate for making an Atari 520ST power supply. Might be good to keep in mind if you have friends in IT, or if you have access to a cheap source. It’s rated for 3A @ 5V, 2A @ 12V, 0.2A @ -12V, and a maximum of 30W. This is...
  11. jdmcs

    3D Printed IBM Case Keys?

    I live in Virginia, so I will probably end up taking the computer to a locksmith if I can’t locate a key. The main locksmith in town has been in business long enough that they might even have the IBM key codes… one can hope.
  12. jdmcs

    3D Printed IBM Case Keys?

    It’s a blade key.
  13. jdmcs

    3D Printed IBM Case Keys?

    I have an IBM PC 365, and I need a key to safely open the case, as I don’t want to break the plastic. However, I can’t find any information on which key fits this case, or where I can get one. Which has me thinking, “Has someone modeled the IBM case keys so that one can simply be printed?” It...
  14. jdmcs

    Who's Going to VCF Swap Meet at InfoAge in June?

    I'm thinking of going to the Silverball Pinball Museum in Asbury Park, NJ the evening before the swap meet, for anyone else that would like to join me. Admission is $18 for one hour or $20 for the rest of the day. I'll probably be there sometime after 7PM. (Note that the parking near the museum...
  15. jdmcs

    Opinion Question: Tale of two CPUs

    If the system has VLB slots that you would like to use, then you want to go the DX4 100MHz route. The reason Intel abandoned the DX 50MHz (so I've been told) is that other chips weren't always reliable at a 50MHz bus speed, though shortages of the DX 50MHz may also have contributed to poor...