Thursday, October 6, 2016

Fixing Apple IIs

Since getting my Apple //c in June 1984, I have been a huge fan of this machines, and I regularly browse Craigslist for machines to rescue. I now have 6 machines of various kinds in my garage, maybe it is time to admit that I have an issue.
Over the last 5 years, I managed to locally find a couple of original Apple IIs, great machines, but both were upgraded to Applesoft roms. Back in 1979, I would have done the same, upgrade to a newer firmware, get new features. I do this with my phone, my car, whatever can be upgraded.  But 30 years later I am trying to get things in their original state.
This means re-installing the original Integer roms. For many hardware fanatics, this is fairly easy, but I am not one of them :)  I had both machines open on my workbench swapping roms right and left, but could not get them to work, various errors, no boot. Removing chips from the board with a screwdriver, installing new ones, testing, back to step 1.


Browsing the 
Apple II Enthusiasts group on Facebook, I got in touch with John who lives close by. He agreed to help me, so I went to see him with my machines, and a bunch of roms to try out. This ended up being a great afternoon, I met a great guy, so knowledgeable of both hardware and software.

Opening Apple II and starting the tests

Home made board to test main logic steps

The machine would boot to a garbage screen, but never complete the process. John used his own board that checks every important chip for i/o, voltage.


Removing each chip and single testing them. Found 2 4116 ram chips in the process

Magnifying glass to look at the board and traces

After checking every chip (replacing 2), the machine is still not booting, time to dig deeper. John opened Understanding the Apple II. This book is a collector item, I had one at some point.  It was nice to see the actual value of the book at work, it is not only an expensive collector item, it is also a very useful book.


Image result for Understanding the Apple II book
Understanding the Apple II



Still not booting
Wile John was deep into following flow diagrams, I browsed his amazing colleciton. If I have a problem with 5/6 Apple IIs in my garage, he has 20, at least....


Finally the error was diagnosed, My screwdriver skills cut traces on the board. Not surprising I admit.


This means it is getting better, I learned. And it is finally booting.




My fixed Apple II running Karateka




 Rebuilding it


14 comments:

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  3. It was nice to see the actual value of the book at work, it is not only an expensive collector item, it is also a very useful book. interior home painting

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  5. I'm really amazed by how you're able to not only find this machines but also restore them so they work again! It must not be an easy feat considering they're really old computers but it seems all that hard work pays off for you. Other thing that amazes me is how good is Wallpaper Installation Phoenix with anything related to wallpapers, that'swhy they became my favorite wallpaper installation service.

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  6. John helped me diagnose the issues with my Apple IIs and showed me some tips and tricks for troubleshooting and repairing them. He was patient and explained things in a way that was easy for me to understand. With his help, we were able to get both machines running with their original Integer roms installed.

    It was a great feeling to see the machines boot up with the original Apple monitor prompt. I had forgotten how different and raw the Integer Basic was compared to the Applesoft Basic. It was like taking a trip back in time.

    Thanks to John's help, I was able to bring my Apple IIs back to their original state, and they are now part of my collection of vintage computers. I have since acquired a few more Apple IIs and have been able to restore them as well, thanks to the knowledge and skills I gained from my experience with John.

    In conclusion, if you are a fan of vintage computers and are interested in restoring them, don't be afraid to reach out to the community for help. There are many knowledgeable and helpful people out there who are willing to lend a hand and share their expertise. https://cincinnatiseo.io/

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  7. The best way to repair a board is to understand the circuit and use an oscilloscope to debug it.

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  8. How do I fix error connecting to Apple ID server . ?

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  9. It's wonderful to hear about your passion for Apple II computers and your efforts to preserve and restore these machines. It's not uncommon for enthusiasts to collect and rescue vintage computers, as they hold a special place in the history of computing.

    Restoring these machines to their original state can be a rewarding endeavor, but it can also present challenges, especially when dealing with hardware modifications and upgrades. It's great that you reached out to the Apple II Enthusiasts group on Facebook and found someone like John who was able to assist you.

    Having someone with knowledge of both hardware and software can be incredibly helpful in troubleshooting and identifying the issues you encountered. Their expertise and access to specialized tools, like the board for testing main logic steps, can make the restoration process smoother.

    It sounds like your visit with John was not only productive but also enjoyable, as you had the opportunity to meet someone who shares your passion for Apple II computers. These interactions and connections with fellow enthusiasts can further enhance the experience and create a sense of community.

    I wish you the best of luck with your restoration projects, and may you continue to enjoy the world of vintage computing! If you have any more questions or need further assistance, feel free to ask. https://junkliberty.com

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