Macintosh SE - Dashed Line, No Boot Chime

[dcr]

I have a goal of owning a functional, usable, original Macintosh SE (with 800k floppy drive and hard drive) and this machine is fighting that kicking and screaming every step of the way.

This machine is assembled from the functional parts of two Macintosh SEs plus the CRT of an SE/30 (that was a complete unit with the exception of a missing logic board).  I don't remember how many floppy drives I've tried to fix just trying to get a working 800k floppy drive for it.

When I last booted it up, which was a couple months ago, it worked fine, with the exception of the floppy drive.  I don't remember if it would read floppy disks; I know for sure it would not eject them.  I decided to boot it up tonight to make notes of what was wrong with the floppy drive.

And now it's not booting up at all.  No boot chime.  It sounds like a fan is running but it doesn't sound as though the hard drive is trying to spin.  No hard drive light, but I don't think that was even working anyway.  The screen just shows a centered horizontal line that's broken into sixteen segments, like: ----------------.

Any ideas what the problem could be?  Or is this machine a lost cause?

Thanks!

 

[SuperSVGA]

Could you perhaps get a picture of it? It might be helpful.

I'd take a guess that the problem is with the Analog board but usually you'd still get a startup chime.

 

[dcr]

Could you perhaps get a picture of it? It might be helpful.

Yes, I'll try to get a picture of it over the weekend.

Basically, it's a white horizontal line that looks about 3-5 pixels high with a 1-pixel width of space dividing it into 16 equal-width segments.

I do have a second SE analog board I can try but I only have one SE motherboard.

 

[IlikeTech]

Try the other Analog board.  That sounds more like a power issue then a logic issue.

 

[dcr]

This Mac appears to be resistant to repair.  

Finally, I had some spare time to work on this computer.  The "power issue" comment stuck in my head, compelling me to think about swapping power supplies rather than analog boards.  With that in mind, I removed the power supply from the donor SE yesterday, which turned out to be a more complicated endeavor than I had anticipated.  So, I decided I would finish the swap today at the office, where I have a large table I can use.  So I hauled both Macs and my tools to the office and commenced the swap.  Wherein I find that the power supply in the once-functional SE was likely removed, if not replaced, once before due to the fact that one screwhead is completely stripped, rendering its removal darned near impossible.  Every method I tried failed.  The last remaining option is to use a rotary tool to cut a slot in the screw to remove it.  And where is my rotary tool?  Not at the office.

And, yes, if I had re-read this thread, I would have tried swapping out the analog boards along with their respective power supplies but, alas, I didn't.

Maybe tomorrow I might have a chance again to work on it.  And possibly discover the next obstacle this machine will throw at me.

 

[dcr]

Qapla'!

I now have a functional (for now) Macintosh SE.  Well, except for the floppy drive but that's what Floppy Emu is for.

I swapped out the power supply, leaving the analog board alone, flipped the switch and, voila!, got a boot chime.  It started up and runs fine.

And then I discovered the "W" key on the keyboard is completely locked and won't budge.  But, it's not a matching keyboard anyway, so I just have to dig out an era-appropriate keyboard and hope the new (old) power supply lasts for a bit.

Thanks for the tips!

 

[dochilli]

Most of the power supplies and analog board need a recap. I think you should try this with your power supply. Perhaps it will work again.

 

[dcr]

Most of the power supplies and analog board need a recap. I think you should try this with your power supply. Perhaps it will work again.

I plan to on both the (now spare) power supply and analog board.

 

[dcr]

Someday, too, I want to give the floppy drive another go.  I don't necessarily need it since I have a Floppy Emu but it would be nice to have it functional for authenticity's sake.  I can't remember now if it will read a floppy disk.  I know it won't eject them.  If the latter is the only problem, it might be the gear that's worn out, but I don't recall any gears looking bad when I cleaned and lubricated the floppy drive.  I should probably try using a floppy in it again to see if it reads it, but I'm hesitant to potentially ruin a good floppy disk.  Good floppy disks are almost like unicorns these days.