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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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