Blogs

 

All members are invited to blog on Applefritter. Weblogs should generally be of a technical nature and should be written in such a way as to still be readable and useful 50 years from now. Please do not embed outside media. Images and videos can be uploaded via the Media Browser. Files should either be attached to the blog post or uploaded to the file libraries.

 

When you post to your blog it will appear on this index and on your personal blog page. Once you've made a few posts, contact me about having a graphic added on the top of this page.


Garbled screen, but progress

So the first thing I tried was swapping the RAM out and that had no effect.  I then had a look at the EF ROM.  Testing it wasn't too difficvult, and with the air of an Arduino and breadboard I descovered that blocks of the rom appeared blank.  I read the rom a few times and the blank areas moved about.  I put a PCB together with a ZIF socket and soldered the connections to make certain the blank areas weren't a loose connection.  I then downloaded the rom, bought an EPROM and turned my reader into a programmer.  However with the faulty rom replaced very little changed, how

First sign of life in over 25 years from my Apple ][e

So the replacement caps arrived today.  It turned out that while one of the tantalum capacitors on the main board had failed short, some actually seemed ok.  However I replaced the lot as a couple more had odd readings and there are only 9 of them anyway.  Powering the board up I actually got some output, though it's garbage with a flashing cursor a 3rd of the way down the screen.  Still, not at all bad for a computer that has sat idle for 25 years.  I'm thinking a short on the data or address bus, or maybe a faulty ram chip.

The resurrection of my Apple ][e

Around 25 yeasr ago (maybe longer) I turned my Apple ][e on and instead of booting I got nothing out of it.  I had a spare power supply so I swaped them over but to no avail.  I put the machine asside to repair and...

 

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