Floppy drive works, SE doesn't. Capacitors suspected.

[Apostrophe]

Hi,

I installed the FDD that Scott Baret sent me, put the other HDD back in, and turned it on...

It rejected my system disk every time.

3 possibilities of malfunction:

a) bad system disk (but it worked fine last week, so I doubt it)

B) bad floppy drive (but that thing looks new; besides, it did eject, so I can see that it works fine)

c) bad capacitors dealing with the FDD

I sincerely believe that I will need to re-cap that SE for it to work well again. I was planning it anyway; really soon I'll be re-capping all of my 15+ year old computers. I read in this forum that capacitor goop can corrode the traces, so I thought I'd replace all capacitors before that happens.

So I'll teach myself how to solder, take that SE apart piece by piece, replace every single capacitor on both the logic board and the analog board with new ones, put it all back together, and see what happens.

-Apostrophe

 

[Scott Baret]

Have you tried another system disk?

Good luck with the re-capping!!!

 

[Apostrophe]

Unfortunately, I don't have another system disk. And I couldn't figure out how to download the Apple website's OS onto a floppy. I didn't even get past the first step; the Centris 610 couldn't properly read my CD!!

-Apostrophe

 

[Apostrophe]

I just now opened my 'working' SE to install its RAM, but I never got that far. Upon close inspection of the board, I noticed that one of the components is completely detached from the board on one side:







Now, I'm used to capacitors being the cylinders that vertically stick up from the board. Is the component pictured also a capacitor? It isn't labeled; how can I know what to replace it with and what its polarity orientation is?

Thanks,

-Apostrophe

EDIT: False alarm. See below. Sorry!

 

[Gil]

I'm no electronics expert, but I think thats a resistor.

 

[joshc]

Apostrophe, that is a resistor not a capacitor.

 

[MrMacPlus]

and that resistor is used to tell the machine how much ram is installed, you're supposed to snip it.

 

[Apostrophe]

Ohh, okay. Thanks, everyone.

Doesn't it ever get on your nerves when...you know how you think you have a good understanding of it all, that everything makes sense, and then you learn some obscure exception to your general rules? Like, when I see a resistor partially disconnected from the board, I automatically think, "Uh-oh. Gotta replace that. How did it get there anyway?"

I encounter these little 'exceptions' very often, and they often make me feel like the 'underdog' (I know that most people on this forum know a million times more than me about computers, but I still like to think of myself as someone who still knows quite a bit) but the good thing is that it expands my knowledge every time I encounter one...

Anyway, sorry for the misconception, and I switched the thread name to the way it was before. And later on I'll go ahead and put that SE's RAM and board back in!

-Apostrophe

 

[Apostrophe]

Okay, just put in the RAM and installed the logic board. Works just fine.

So out of my two SE's, one is working perfectly. The other one (the one that I first posted about in this thread) I believe to work but I need another system disk to be sure, since it doesn't like the one I have.

-Apostrophe

 

[equill]

and that resistor is used to tell the machine how much ram is installed, you're supposed to snip it.

... if the machine has more than such-and-such MB installed while it is active, which is something that Apostrophe needs to be aware of.

1 MB

• Install four 256K SIMMs.

• Leave resistor R35.

• Remove resistor R36.

2 MB

• Install two 1 MB SIMMs (Slots 1 & 2).

• Remove resistor R35.

• Leave resistor R36.

2.5 MB

• Install two 1MB SIMMs (Slots 1 & 2.)

• Install two 256K SIMMs (Slots 3 & 4).

• Remove resistor R35.

• Remove resistor R36.

4 MB

• Install four 1MB SIMMs.

• Remove resistor R35.

• Remove resistor R36.

Note: For a 2.5 MB configuration, clip one lead of the resistors and move the resistor out of the way so it can be reinstalled if necessary.

de

 

[Apostrophe]

Thanks equill,

Both R35 and R36 have been previously removed by whoever expanded the RAM, as per my pics.

I'll add this 'resistor clipping' to my ever-expanding knowledge of vintage Macs.

-Apostrophe

 

[joshc]

Well I learned something today (and I've only just got up) - thanks Equill.