What went 'pop'?

[Apostrophe]

My 512k popped when I tried turning it on--see my thread in Conquests, esp. my latest post in that thread:

viewtopic.php?f=3&t=9678

So I opened the case to see what went pop. Everything still looks pristine. I know I can rule out the logic board, seeing as when I looked it over, it looks just as I left it. It's mostly chips anyway, and I don't think those would go pop.

Obviously it's the analog board, but I still couldn't see which component blew. All capacitors are still flat on top, and shiny. Everything looks complete and gunk-free.

And then I spotted a weird large component labeled Astec, with the number 157-0025-A printed on the label.

It's the big orange component in this picture of JDW's:




What does this component do, and is it something that could have popped?

-Apostrophe

 

[Megas3300]

That is the low voltage transformer. It usually has a layer of gunk on it.

 

[JDW]

...is it something that could have popped?

No. Capacitors "pop." And remember there are some capacitors on the logic board too.

 

[Megas3300]

See if you can see anything under the capacitors, some are designed to vent that way. I don't know if they use any in a 512k however.

 

[Apostrophe]

The capacitors on both the logic board and the analog board all look fine, but of course, it isn't easy giving the underside of capacitors on the analog board a good look without removing the analog board (which I only want to do if I'm replacing it with another--which is my plan.)

In about a month, when it's my birthday and I'll have more money, I'll order a replacement floppy drive (since this one won't read disks) and a replacement analog board. And then, when I switch out the analog boards, I'll know for sure if it was indeed the problem.

Updates to come then!

-Apostrophe

 

[stevep]

Just a thought re the floppy drive....

In your first post you mentioned the floppy disk it was shipped with pops back out. Is this why you say it won't read a disk or have you got a disk to stay in now? If it won't stay in, then you can fix this floppy drive - it's all the old, hardened grease that's the problem. I fixed up two recently that had this problem; it took some time and patience but now they work fine.

Check the topic "Unjamming a 400K floppy drive" in the Compact Mac section. Equill provided a link that was very helpful in this regard.

 

[Danamania]

I know I can rule out the logic board, seeing as when I looked it over, it looks just as I left it. It's mostly chips anyway, and I don't think those would go pop.

Chips can definitely pop (sometimes loudly) http://en.wikipedia.org/wiki/File:No_blue_smoke.jpg was one of mine on a HD, and I had a voltage regulator in a Q840AV explode too, in a rather more dramatic manner.

Dana

 

[Apostrophe]

Danamania--wow. I never knew that could happen...

Stevep--no, I think it was just because they didn't push it in all the way. Back when the 512k powered up ( ) I would push a known working 400k software disk into the drive all the way, where it stayed. But not a peep from the floppy drive. No sounds, and all I had to do was reach in and pull the disk back out. (Well, sometimes it did stay in tightly, which was where the manual eject hole came in handy.) The only sign of life that floppy drive shows are red LEDs on inside it. But apart from that--nothing.

-Apostrophe