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Hi 68kLBA,
 
I am new here. My name is Jeff Ramsey. I am a 38 year old IT professional, and I've been in the business around 20 years. When I was a kid in school, my first experiences with computers were with my grandmother's Commodore 64, and then I got my own Commodore 64. In grade school, we did not have Commodores, we had Apple II or Mac 512s. I envied those machines so much! They were way out of my price range, but man they were cool!
 
Anyhow, now I have three kids and we love to play both current and retro games. At the same time, I wanted a project to do at home. Sort of a computer "hobby" project. SO I decided to start by refurbishing a Comact Mac. (Starting to sound more like my first day at Alcoholics Anonymous than my first post here at this point, huh? HI, I'm Jeff, and this is where I screwed up...)
 
I bought an SE (FD/HD model 5011) from an elderly lady's closet. (Don't ask what I was doing in a 90 year old lady's closet.) It had been sitting for years. It powered up, the screen was clean, a little bit of screen burn, but clearly working. It was asking for a floppy. I paid $40 and took it home. I made some System 6.0.8 disks and it booted and ran! I didn't remember the date or time (dead battery) and didn't see the hard drive at all. I made a disk for "The Oregon Trail" and played all the way through with my daughter. We made it to Willamette with 3 of our 5 still alive. Yay!
 
Now I wanted to upgrade the 1MB ram to 4MB and I wanted to fix the hard drive, so I made a 12" long T15 (my friend made the tool with a short bit and a bit of round stock steel. Thanks Tyler.) and opened her up. Here is what I found:
 
HfzaKR1.jpg

 

I wasn't prepared to deal with this bad of a battery issue last night, so I just installed the RAM chips, changed the jumper for the RAM, replacement hard drive then buttoned her back up. What I got was discouraging. The hard drive still does not show up in SC HD Setup, and although the memory is showing 4mb now, the machine is crashing randomly now. It will run for a few minutes and then either a "bomb" system error or just freeze up.

 

I am getting ready to clean the entire mainboard here in a few minutes. I looked at all of the caps and they all looked ok, non were burst or bulging, but I will look at them again more closely. Aside from that, is there anything that I am looking for?

 

Thanks

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I would remove the battery immediately so it doesn't damage anymore. I would then wash the entire area with like 20% ammonia mixed with distilled water to neutralize the acid and pick up the residue. (using cotton swabs)

 

You can then just buy a replacement cap. Is it one of the two axial capacitors (lead coming out of each end)

 

You can also clean the entire board with alcohol to clean up any additional residue and dust

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No! The Maxell bomb has yet another victim. I can check my SE board when I get home this evening to see what C10 is. You should be able to see uF and voltage rating on the cap itself. Digikey or Mouser will have replacements. Get that board cleaned, and fast! Be gentle and check for corroded traces and pads. Give the board ample time to dry before you reinstall it. The SE boards are pretty robust. You can replace the other axial caps if you want, but I don't think it's necessary at this point. Priority would be removing the battery and corrosion, repairing any resulting damage, then replacing the bad cap, battery holder, and battery with new components.

Edited by SlateBlue
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I removed the battery. The metal contact on the left side of the battery in the picture just fell off as soon as I tried to move the battery at all. I cleaned the board with electronics safe and plastic safe contact cleaner. Should I use alcohol instead? Anyhow, every since I added the 4mb of RAM, the machine has become unstable, giving me "address error" and freezing up randomly. I got this RAM from a junk bin, so I am going to revert back to the four 256k sticks that it came with and see if that is the issue.

 

Any ideas why the hard drive will not show up? I have verified that it has power. I have booted from a patched 7.3.5 boot disc and tried to initialize it, and SC HD Util does not "find any suitable scsi drives". I have checked the drive jumpers and they are set to SCSI ID 0 and parity checking is enabled.

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That depends... It could be a problem with either your logic board or with the hard drive. Just because a drive has power doesn't mean it'll send data.

 

The easiest way to figure out the point of failure is to test the drive with another board or computer, or test another drive with your board.

 

I think it would be preferable if the Hard Drive was the point of failure, although the battery corrosion makes me think it's possibly on the Motherboard side of things (but I'm hardly the best at guessing). I don't believe the SE shipped with disks that were prone to getting their rubber stoppers gummed up (I think the SEs used the older stepper motor disks), but it's a possibility, in theory.

 

Either way, I second this "get the board cleaned right now and do damage control" stuff. The longer you wait, the more likely the board will be damaged. Battery guts truly are the worst, even worse than cap goo  :(

 

On the RAM side of things: Luckily for you, new RAM is relatively cheap, so if you want to upgrade to the full 4 megs and the RAM is really the cause of your instability, it won't be very expensive. Other problems could include a crappy system install (try using another bootdisk or system version and see how you fare).

Edited by macosten
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These boards have a jumper or resistor that needs to be changed to allow for different memory configurations. Most later revision SE boards had a jumper. See this page for more info: http://www.ccadams.org/se/ram.html

 

 

Thanks. I did know about the jumper and I removed it when I put the four 1mg sticks in. I actually found that same article with google last night when I was preparing for the job.

 

That depends... It could be a problem with either your logic board or with the hard drive. Just because a drive has power doesn't mean it'll send data.

 

The easiest way to figure out the point of failure is to test the drive with another board or computer, or test another drive with your board.

 

I think it would be preferable if the Hard Drive was the point of failure, although the battery corrosion makes me think it's possibly on the Motherboard side of things (but I'm hardly the best at guessing). I don't believe the SE shipped with disks that were prone to getting their rubber stoppers gummed up (I think the SEs used the older stepper motor disks), but it's a possibility, in theory.

 

Either way, I second this "get the board cleaned right now and do damage control" stuff. The longer you wait, the more likely the board will be damaged. Battery guts truly are the worst, even worse than cap goo  :(

 

On the RAM side of things: Luckily for you, new RAM is relatively cheap, so if you want to upgrade to the full 4 megs and the RAM is really the cause of your instability, it won't be very expensive. Other problems could include a crappy system install (try using another bootdisk or system version and see how you fare).

 

This is good advice. I have two drives, but I don't know if either are any good. I have the one that came with the machine, and the one I bought from a guy on CL with the keyboard that I bought. Both have the same issue, they are not detected. I do not have another Compact Mac just yet. I am hoping to get another one soon though.

 

I tried three different sets of 1mb sticks and they all had the same issue. Right now I am back on my four 256k sticks and the machine is stable again. It has been running from the same 6.0.8 boot disk for 30 minutes now, with no freeze ups or "bomb" system errors. So it does not like any of that other RAM. It is all 70ns speed and all except two sticks are 3 chips per stick, so maybe it is just too fast or not compatible with the machine? Perhaps I could try to run just the two 2mb sticks that are 9 chip. Will it run on two sticks or does all of the slots need to have something in them like RAMBUS? (Of course I would set the jumper to 2M/4M setting?)

 

I will get ahold of some ammonia and make the cleaning solution asap. I did remove the battery and used elec+plastic safe contact cleaner on the entire area to try to clean the area quickly. I don't know how well that stuff will neutralize the acid though.

 

Thanks for all of the help.

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I'm not entirely sure, but I think I remember hearing somewhere that SE's need ram with 8 or 9 chips per piece as opposed to two or three, so that very well could be it. I think you could try the configuration with the two 1MB sticks with the right number of chips in the back two positions, and two 256k chips in the front two. There is a jumper setting that allows that configuration, I believe, and it should work.

 

Also, congrats on the SE! It was my first compact Mac and still my favorite of my computers. Hope you get everything resolved!

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Depends on what hard drive you have, if you have an early quantum or a Miniscribe, both are known for failure and its entirely expected at this point. 

 

Best thing for future use is a SCSI2SD and prep up an SD card with a bootable system and some games, and let her rip. 

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Depends on what hard drive you have, if you have an early quantum or a Miniscribe, both are known for failure and its entirely expected at this point.

 

Best thing for future use is a SCSI2SD and prep up an SD card with a bootable system and some games, and let her rip.

 

The drive that came with it is a Miniscribe and the one I got from the Craigslist guy is a Quantum 40mb. Lol. It's like you have been watching me. You really know what I am going through here. My Craigslist friend did say that the Quantum was tested and working.

 

I like the idea of the scsi2sd card but I have not decided to put that much money into this computer until I can get everything else working on the computer. Once I have everything working, I would love to install a scsi2sd card. I have a ton of smaller SD cards that are not good for much else.

Edited by jefframsey
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Oh no Maxell batt... Your lucky it didn't do that much damage... I think we've all seen much, much, worse..  I prefer the Aztec PowerMonster from the gentlemen in Japan off ebay.. Haven't seen them much.. But just tried my first SCSI2SD and it's not bad.. as everyone said.. most of all the old hdd's will fail soon... and after loading things on it will happen at the most worst moment. So an upgrade to a flash replacement is probably best..

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  • 68kMLA Supporter

SE FDHD was also my first machine to get my hands on. I think I paid $25 in 1995 for it. I found a 3Com network card a few months later. Since then I'm "obsessed" with networking Mac's. So a network card could ba nice step in your new hobby!

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The drive that came with it is a Miniscribe and the one I got from the Craigslist guy is a Quantum 40mb. Lol. It's like you have been watching me. You really know what I am going through here. My Craigslist friend did say that the Quantum was tested and working.

 

 

 

Its not that I watch you, its the same old tune I see over and over again with these machines. They ALL have these exact or similar issues. And Just because the craigslist guy said the Quantum was tested and working, thats usually it. 

 

They tend to work once, or twice, then quit. Its because there is a rubber stop inside the hard drive that turns sticky and will hold the actuator arm from being able to move. Depending on which version of the mechanics are in that drive, its repairable IF you know what your doing. 

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Its not that I watch you, its the same old tune I see over and over again with these machines. They ALL have these exact or similar issues. And Just because the craigslist guy said the Quantum was tested and working, thats usually it. 

 

They tend to work once, or twice, then quit. Its because there is a rubber stop inside the hard drive that turns sticky and will hold the actuator arm from being able to move. Depending on which version of the mechanics are in that drive, its repairable IF you know what your doing. 

 

TechKnight is 100% correct. He really knows what he's doing, though to be fair this particular issue is really common - I, for example, have a disk like yours that has failed similarly, where it worked once, but then it wouldn't work again. Listen to the drive closely when it powers up - does it spin up, and then seem to "give up"? If so, this is probably your problem.

 

It's possible to "fix" the drives, but adapting this method into a permanent fix by, say, putting masking tape on the offending rubber stopper (or even attempting this fix at all), is very tricky and could easily fail. Thus, I'd say that SCSI2SD is a superior long-term solution.

 

Off Topic Addendum: Tech, I hope you do a 1000 sub video for your YT channel, 'cause you're up to 992. :)

Edited by macosten
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Its not that I watch you, its the same old tune I see over and over again with these machines. They ALL have these exact or similar issues. And Just because the craigslist guy said the Quantum was tested and working, thats usually it. 

 

They tend to work once, or twice, then quit. Its because there is a rubber stop inside the hard drive that turns sticky and will hold the actuator arm from being able to move. Depending on which version of the mechanics are in that drive, its repairable IF you know what your doing.

 

I really meant that as a compliment. Because you know so much about what I am going through with this machine that you are just as helpful as if you were here with me in person. All of you do really.

 

Anyways...

 

I just finished giving the entire logic board a scrub in 20/80 ammonia and distilled water, followed by a good scrub in 91% isopropyl. It is hanging up to dry over the weekend as I take my wife away for our wedding anniversary. I did remove the battery the other day but I have not removed the battery holder yet. It never dawned on me that there are traces underneath the battery holder. On Sunday I may try to unsolder the battery holder and then clean that area again.

 

As far as the hard drive, I will check when I put the logic board back in to see if it spins up and then stops or if it spins up and stays spinning.

 

This machine will rise again! I have collected a good amount of software for it now and I need to get a hard drive or scsi2sd so that I can install some of this stuff.

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I need to order the battery and holder but I also need to order the bad capacitor. Problem is, I cannot read the writing on it. It is labeled C10 on the logic board and it is right above the speaker connector.

 

Before I removed the battery, the startup sound was working, but was a bit weak and distorted. When I removed the battery, one leg of C10 axial cap came off with it because it was stuck with rusty battery guts to the battery itself. Ever since then the startup sound is completely gone.

 

Can anyone tell me what the specs are on this capacitor? It looks the same in size and color as many of the other smaller capacitors on the board.

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Since then I'm "obsessed" with networking Mac's.

 

Yeah, this is pretty much me as well.

 

Anyway, jefframsey, welcome to the forums. It's always nice to see others expanding the hobby. I won't repeat what others have said, but simply echo their suggestions to make cleaning the board a top priority. Simply wiping affected areas with a swab and cleaning solution may not be enough. You need something to neutralise the battery leakage, and I'd actually stick that entire board into the dishwasher once all the removable components are extracted. Alternatively, a bucket of water with a bit of washing up liquid will do the trick. Spend some time with a toothbrush and/or paintbrush working around all the nooks and crannies. Then get that board drying for *days* using whatever method you like. That should help clear things up enough so you know what you're dealing with.

 

I would then consider taking a look around the battery compartment and see what areas have been affected by the leakage. You gotta hope traces and vias haven't been rotted through. Moving outside of my particularly skill set, it is likely advisable to get a voltage meter out to see what (if any) traces have gone bad. It's worth recapping the entire board as well.

 

Compared to some of the others on these forums, I still consider myself to be quite an amateur at this stuff. However, the things I've described above represent some of the tricks I've learned from this forum (and others) over the years that have definitely helped me out quite a lot. Best of luck with this new project and I look forward to hearing how things turn out for you.

Edited by LazarusNine
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The cap looks to me like a 0.1uF 50v based on a Google of 'macintosh se logic board close up' and they had the yellow ones with a 104 marking.

 

What are the colors on the ones you have?

The are orange on the ends and brownish-grey in the middle. Would they be the same as the yellow ones in your picture? Mine looks exactly like the C10s in these pictures:

 

http://www.ccadams.org/se/SE-800k-logic.jpg

 

https://upload.wikimedia.org/wikipedia/commons/6/65/Apple_Macintosh_SE_Main_PCB.jpg

Edited by jefframsey
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yep, 100nF capacitors are used to decouple the power supply. the inrush of current required to overcome the capacitance of the bus to switch the state between 0 -> 1 and vice-versa requires a "storage tank" capacitor directly coupled with it to supply the current. Otherwise the switching spikes would end up on the rails and back in the power supply. aka... noise!  

 

The power supply itself and its rails/traces cannot because of the parasitic inductances. But at certain frequencies the capacitor acts like it doesnt exist so thats why you so commonly see them coupled together as a 0.1uf and 10uf electrolytic. 

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