Hello everyone and thanks in advance.
History:
1. Picked up an Apple IIe (enhanced version) to restore.
2. Booted to message and beep but, had infinite repeating key problem.
3. Repaired repeating key problem, booted with message and peep. Also, played a couple of games but, noticed it didn't pass RAM test.
4. Removed RAM and replaced with sockets and new faster RAM.
5. Now it boots to a screen full of garbage and no beep.
Original RAM chips were MT 4264-20 type with (8520N script in top corner)
Replaced with MT 4264-10 type with (8817 A script in top corner)
** After the fact I noticed the MT 4264-10 RAM was 64k x 8 **
Removed the MT 4264-10 and replaced it with MT 4264-15 (433 script in top corner)
No change, still boots to garbage on screen and no beep.
Question:
Did I fry one of the other chips with the 64k x 8 RAM and is the MT 4264-15 (with 433 script in top corner) compatible with MT 4264-20 (8520N script in top corner)?
** The address and data pins on the CPU now have incorrect wave patterns as well **
~Stapler
History:
1. Picked up an Apple IIe (enhanced version) to restore.
2. Booted to message and beep but, had infinite repeating key problem.
3. Repaired repeating key problem, booted with message and peep. Also, played a couple of games but, noticed it didn't pass RAM test.
4. Removed RAM and replaced with sockets and new faster RAM.
5. Now it boots to a screen full of garbage and no beep.
Original RAM chips were MT 4264-20 type with (8520N script in top corner)
Replaced with MT 4264-10 type with (8817 A script in top corner)
** After the fact I noticed the MT 4264-10 RAM was 64k x 8 **
Removed the MT 4264-10 and replaced it with MT 4264-15 (433 script in top corner)
No change, still boots to garbage on screen and no beep.
Question:
Did I fry one of the other chips with the 64k x 8 RAM and is the MT 4264-15 (with 433 script in top corner) compatible with MT 4264-20 (8520N script in top corner)?
** The address and data pins on the CPU now have incorrect wave patterns as well **
~Stapler