Macintosh Plus floppy message issue

[bibilit]

Hi, have a strange issue in one Plus.

Working ok, booting from HD or floppy but displaying the message « disk not readable - erase or eject »

The message is coming again and again, whatever the erase or eject button is selected.

The floppy is not the issue, tested and working fine in another unit, more a Logic board issue.

 

[LaPorta]

It is likely somehow "seeing" a drive connected to the external floppy port, I would surmise. If you have the Macintosh Family Hardware books, look through how the lines of the Plus' floppy port works, and try and look for a solution there. That is what I would surmise, at least.

 

[bibilit]

I wasn’t thinking about the rear connector, but yes can be the issue. Thanks

 

[LaPorta]

I hope it leads to something. Let us know what you find!

 

[bibilit]

The more i think about it, the more i believe this is related with one of the Bourn filters... will let you know

 

[LaPorta]

The more i think about it, the more i believe this is related with one of the Bourn filters... will let you know

I can’t believe I didn’t mention that…I thought it yesterday and didn’t say it. I had that happen once with a filter failure.

 

[bibilit]

I have got a damaged spare board, so i will swap parts.