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SE/30 Floppy Issue
Posted by: Eric672 on 2019-02-08 07:47:31
Hi! I recently got my SE/30 logic board recapped and I am having an issue with it reading any floppy disk I put in the drive.  Prior to the recap it wouldn't boot.  Now it boots and I can load/run from the rominator ii and everything appears to be stable...just can't get floppy's to load/read.  I have swapped out the drive with 3 other known working ones as well as the ribbon cable and the system just ejects any inserted disk with question mark floppy icon on the screen.  So at this point I am thinking there has to be an issue on the logic board itself.  I am not great at troubleshooting things on a logic board so any help would be greatly appreciated.

Posted by: clh333 on 2019-02-11 10:03:09
The ROMINATOR II uses a flash-RAM - based image to boot, and so is using different logic-board circuitry than the floppy disks would.  The fact that the machine boots from the RAM disk and not the floppies - especially given that you have substituted drives and cables - strongly suggests a problem with the logic board.  Without knowing more about the sequence of events or any dialog boxes that may appear it's hard to say for sure, but there are some things you can check if you have a simple Ohmeter:

According to Larrry Pina's Mac Classic and SE Repair and Upgrade Secrets, (Peachpit, c. 1993) P. 87-89, the problem may be related to a bad filter at board ref. RP10.  This part is Bourns 4120R-601-250/201.  The book describes the test procedure and gives a table of acceptable and unacceptable measurements.

If you can't manage the tests yourself, perhaps the shop that did the recap work could do it for you.  After all, they were supposed to test the board fully before sending it back to you, weren't they?

Good luck! 

-CH-

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