Recent content by jdmcs

I'm going to try to make it to the VCF Swap Meet in NJ this time around. (I am also 99.9% sure I'll be at the System Source Swap Meet next weekend.)

I've seen these power supply upgrades in photos, but not in person - they were part of some upgrades because the original power supplies had little margin for upgrades. I suspect there was an accelerator card in this Mac Plus that has been removed, as normally you wouldn't be able to install an...

Have you re-capped the logic board? If so, you might want to inspect for shorts around the replaced capacitors, especially if you used tantalum capacitors with a shorter pad spacing than the original electrolytic capacitors. You might also check out this video from Adrian's Digital Basement...

Have you recapped the Delta power supply? I have had two, and they both had leaking capacitors. Note: They're not fun to re-cap. Measuring the voltages of these power supplies is a pain, as they plug directly into the logic board. I've done it before by putting the power supply on it's side so...

I am having trouble finding technical documentation on the IBM Portable Personal Computer 5155 (which I'm going to simply refer to as the 5155 from here on out) in regards to the voltages that the analog board can output to the CRT. And from seeing Adrian Black try to repair a terminal recently...

I realize the answer could be that I bought a PC Cheaps... I mean, PC Chips motherboard on eBay, and a 50% POST-on-power-up ratio should be considered good. However, this issue could extend to other boards, and maybe there is another issue that is the cause. I have a PC Chips M326 V2.7...

I didn't think the pins on the keyboard connector would fit in a machined socket, but I just found one that I had on hand, and the pins appear to fit. I'll just have to get some in DIP-16 size next time I order from Mouser. I'm not sure if a ZIF socket would fit. If I can find dimensions of a...

On the Apple II series, Apple used a different DIP socket for the keyboard, game pad, and for the Apple II and II+, the memory chip at E3. It was a socket designed to accept an IDC ribbon cable with a DIP plug. I need three of these sockets, and I’m having trouble finding them partially because...

It's close - it has two tabs and doesn't appear to be retained by a screw (probably just the motherboard keeping it in place). Here's a crop of the photo of the one I bought: I'll get better photos once I receive the case.

Hi, my name is Justin D. Morgan, and I’m running for re-election to the Tinker Different Board of Directors. I am currently serving on the board as the Director of Policies and Guidelines. In this role, my responsibility has been to propose any needed changes to the policies and guidelines for...

Or it was user error on my part. I was able to install a standard I/O shield by starting with the bottom edge. To be fair, there could be some mechanical variances between cases that make it harder to install a standard I/O shield on some cases. I have a second case on the way that I can use to...

I just bought an A500 case with an I/O shield, so hopefully I'll have a shield for taking measurements of within a week or two.

Update: Apparently, despite having installed countless ATX I/O Shields over the past 25 years or so, I did it wrong. Apparently, I should have started with the botton edge, then pushed the two sides in, and finally pushed the top side in. If you start with the top edge, you won't have enough...

The current CONFIG.SYS is as follows: DEVICE=C:\DOS\HIMEM.SYS /TESTMEM:OFF DEVICEHIGH=C:\DOS\EMM386.EXE 2048 AUTO DOS=HIGH FILES=30 And the current AUTOEXEC.BAT file is a blank file.

So I forgot to try to load EMM386 high, but the parameters “2048 AUTO” only changed the symptoms slightly. DOS 6.22 was able to finish booting, but I started getting general failed errors on C: after a few disk accesses… It’s not the disk (it doesn’t happen when I don’t load EMM386). I’m...