Juror22
Well-known member
This summer I have been checking in on all my Mac II family that I have gathered together over the years and put an effort into ensuring that each one of them is cleaned, serviced, setup and working correctly e.g boots and shuts down correctly, has sound, floppy functionality, etc.
The last time I looked at this, I put together some notes on items to check out and after I had gone through that list and taken it down to the bare board, washed it, re-capped it, and fixed specific, suspect areas of corrosion, I had started the process of re-installing the chips and discovered what appeared to be a broken pin on the underside of the Marathon 030 card.
Since some pins can be redundant (I've, read - although maybe not so much on older chips) or perhaps not needed for the upgrade (and purposely removed?) I'm not sure whether this prevented the Mac II from booting earlier, or its just a corroded via I still need to spot. I've gathered what I believe is valid information and I would appreciate anyone's thoughts on how to proceed with checking out and possibly repairing the pin issue. Here's what I have:
(picture of the Marathon card, 020 pinout with the missing pin marked and the function it performs...)
Here is a picture of another person's Marathon card for sale and at first I thought it had same pin 'missing' in the photo (2nd row from the top, 6th pin from the Left) but now I am convinced that the pin is there and just slightly bent, so that it is in the same line as those in the first row.
I've seen a couple of options for attempting repairs to the pins (basically soldering a pin extension to the cut-off end of the pin or physically jamming a short pin into the socket that makes contact with the cut-off end of the pin) - either of which might work. I'm leaning toward the solder method for long-term stability and worst case, maybe I will look for an 020 and convert it back, since it looks like the functionality of that pin is required, but If there are any alternative suggestions or anyone with experience that would have tips to provide, please let me know.
The last time I looked at this, I put together some notes on items to check out and after I had gone through that list and taken it down to the bare board, washed it, re-capped it, and fixed specific, suspect areas of corrosion, I had started the process of re-installing the chips and discovered what appeared to be a broken pin on the underside of the Marathon 030 card.
Since some pins can be redundant (I've, read - although maybe not so much on older chips) or perhaps not needed for the upgrade (and purposely removed?) I'm not sure whether this prevented the Mac II from booting earlier, or its just a corroded via I still need to spot. I've gathered what I believe is valid information and I would appreciate anyone's thoughts on how to proceed with checking out and possibly repairing the pin issue. Here's what I have:
(picture of the Marathon card, 020 pinout with the missing pin marked and the function it performs...)
Here is a picture of another person's Marathon card for sale and at first I thought it had same pin 'missing' in the photo (2nd row from the top, 6th pin from the Left) but now I am convinced that the pin is there and just slightly bent, so that it is in the same line as those in the first row.
I've seen a couple of options for attempting repairs to the pins (basically soldering a pin extension to the cut-off end of the pin or physically jamming a short pin into the socket that makes contact with the cut-off end of the pin) - either of which might work. I'm leaning toward the solder method for long-term stability and worst case, maybe I will look for an 020 and convert it back, since it looks like the functionality of that pin is required, but If there are any alternative suggestions or anyone with experience that would have tips to provide, please let me know.
