Thread
Classic II cure not so curative - a mininovel with photos :P
Hi there.
Meet my Macintosh Classic II.
It has been behaving rather badly lately, displaying a checkerboard pattern on the internal CRT whenever I fire it up. At this rate, the most useful thing from this Liberation might have been the single solitary HyperCard diskette that was in its superdrive!
Here is a picture of the infamy it displayed. :simasimac:
A little internet research revealed that the problem was a well-known fault due to the SMT electrolytic caps deciding they were ready to die spectacularly.
So, what course of action should I take, other than to bust out my labcoat and soldering iron, and attempt a recap of the board!
That's all and very well when you have the knowledge to pull it off - I didn't. This was my first repair job that actually required extensive resoldering, and I was only "fairly sure" my replacement caps were actually still working.
I gathered up a list of capacitors that were needed and found them in my junk box:
Unfortunately, It appears I have made things significantly worse with my attempt. xx( xx( xx( xx( xx(
Here are some photos of the board :
The caps near the sound hardware that tend to leak most obviously, from what I've read, replaced with electrolytics of equal value.
The caps near the RS422 controllers and near the RAM - I don't know what they do exactly but I replaced them anyway, because they were leaking also.
The fully reassembled logic board, after being very carefully cleaned, reseating the ROMs and the RAM SIMMs ...
The problem I now face is that on switching on the Classic II, I hear the fan spin up, and nothing else. No chime, and furthermore, I don't see ANYTHING on the CRT where once there was a nice ready-made chess board
Has anyone here any ideas what this particular failure mode likely means? If higher-res photos of the board are needed, I can do that easily. I'd just like my Classic II working.
I'm going to be getting some new SMT caps at some point, in case my caps are just bad, but i've no idea how to solder SMDs so that might be a bit pointless.
Also, if I screwed something up while soldering I'd like to know before I spend $20 on a set of replacement caps ( yes, they're that expensive here for tants! - I might have to see if trag will ship me some and how much it would cost... )
So, I ask you all, any ideas?
Meet my Macintosh Classic II.
It has been behaving rather badly lately, displaying a checkerboard pattern on the internal CRT whenever I fire it up. At this rate, the most useful thing from this Liberation might have been the single solitary HyperCard diskette that was in its superdrive!
Here is a picture of the infamy it displayed. :simasimac:
A little internet research revealed that the problem was a well-known fault due to the SMT electrolytic caps deciding they were ready to die spectacularly.
So, what course of action should I take, other than to bust out my labcoat and soldering iron, and attempt a recap of the board!
That's all and very well when you have the knowledge to pull it off - I didn't. This was my first repair job that actually required extensive resoldering, and I was only "fairly sure" my replacement caps were actually still working.
I gathered up a list of capacitors that were needed and found them in my junk box:
- C3 47µF, 16V
- C4 47µF, 16V
- C5 10µF, 16V
- C6 10µF, 16V
- C7 10µF, 16V
- C8 10µF, 16V
- C9 1µF, 50V
- C10 10µF, 16V
- C11 10µF, 16V
- C12 10µF, 16V
- C13 47µF, 16V
- C14 10µF, 16V
- C15 1µF, 50V
Unfortunately, It appears I have made things significantly worse with my attempt. xx( xx( xx( xx( xx(
Here are some photos of the board :
The caps near the sound hardware that tend to leak most obviously, from what I've read, replaced with electrolytics of equal value.
The caps near the RS422 controllers and near the RAM - I don't know what they do exactly but I replaced them anyway, because they were leaking also.
The fully reassembled logic board, after being very carefully cleaned, reseating the ROMs and the RAM SIMMs ...
The problem I now face is that on switching on the Classic II, I hear the fan spin up, and nothing else. No chime, and furthermore, I don't see ANYTHING on the CRT where once there was a nice ready-made chess board
Has anyone here any ideas what this particular failure mode likely means? If higher-res photos of the board are needed, I can do that easily. I'd just like my Classic II working.
I'm going to be getting some new SMT caps at some point, in case my caps are just bad, but i've no idea how to solder SMDs so that might be a bit pointless.
Also, if I screwed something up while soldering I'd like to know before I spend $20 on a set of replacement caps ( yes, they're that expensive here for tants! - I might have to see if trag will ship me some and how much it would cost... )So, I ask you all, any ideas?
Double check your work (make sure the + and - of the capacitors is in the correct spot). The video needs the 1uf 50V capacitors to work. No bong means either the capacitor on the sound circuit is messed up, or you might not have the RAM correct in the socket.
The board has the positive side marked. They look correct from what I can see on the markings on the PCB. But that soldering job .. I am not going there.
Please do go there. It's rubbish, I know that. I was actually wondering if cold solder joints (it was very difficult to work on that board with my iron) could possibly be to blame.
Ok... an update.
I decided the solder joints probably didn't take due to me not cleaning the pads after desoldering, and hence them possibly having electrolyte still on them.
This was borne out when i desoldered all the replaced caps and found many sticky points, so I'm now going to wash those areas.
In the process of desoldering, I accidentally ripped out the positive pad on capacitor C8 (10µF, 16V) - I'm sure I don't need to explain why I feel really bad about that.
Can anyone here tell me where it connects? Or, advise me of a way to safely get the trace reconnected to the cap?
I decided the solder joints probably didn't take due to me not cleaning the pads after desoldering, and hence them possibly having electrolyte still on them.
This was borne out when i desoldered all the replaced caps and found many sticky points, so I'm now going to wash those areas.
In the process of desoldering, I accidentally ripped out the positive pad on capacitor C8 (10µF, 16V) - I'm sure I don't need to explain why I feel really bad about that.
Can anyone here tell me where it connects? Or, advise me of a way to safely get the trace reconnected to the cap?
Ok... another update.
I've scraped off the solder mask over that via that leads to C8 very delicately, and tried to solder a wire to it. bad idea - the wire wouldn't stay in place as the solder was heating up . Long story short, I ripped out the top of the via connected to C8 + by accident. Can anyone tell me where it leads, so I can manually connect it please?
EDITI've now also lost C4's negative lead...
is there any hope?
Seems like you've nuked the classic II as I have.
I can sell you my classic 2 Lobo if you want. I think it has leaky caps, but it's stock. The Analog board on mine is nuked.
I can sell you my classic 2 Lobo if you want. I think it has leaky caps, but it's stock. The Analog board on mine is nuked.
Also, I'd like to say, your Avatar is the absolute coolest thing I have ever seen. Source?
some person on deviantArt who did it. it's a 512*512 png - I personally converted it to a finder icon
Other than that you're in NY, that sounds pretty cool ... maybe I'd screw that one up less. I should really buy some recaps off trag. the electros I used can't have done much good.
How much would you want to sell said logicboard for? (Note, I can't guarantee this will happen, because of varying factors the most of which is "my parent needs to approve everything" but I would love to buy the board from you.)
It's light I guess.
BUT I do not know if it works or not, no guarantee.
BUT I do not know if it works or not, no guarantee.
for future reference, to solder onto small items, such as pcb traces, clean off the mask, tin (that is apply a tiny amount of solder) to the pad, tin the wire THEN just melt the 2 together, also dont use big fat wire on tiny traces, use something like a single strand of a floppy disk cable, or wirewrap wire
Those are through-hole leads and vias, correct? :?:Ok... another update.
I've scraped off the solder mask over that via that leads to C8 very delicately, and tried to solder a wire to it. bad idea - the wire wouldn't stay in place as the solder was heating up . Long story short, I ripped out the top of the via connected to C8 + by accident. Can anyone tell me where it leads, so I can manually connect it please?
EDITI've now also lost C4's negative lead...
If so, you've soldered the wrong side, pre-SMT boards of that vintage were "Wave Soldered" and any connection in a through-hole doesn't actually need the top pad unless there's a surface trace connected to it. In that case, repair the damage with a rework patch (those little pieces of wire commonly found on old boards, either coupled with an intentionally cut trace to remedy faulty PCB Design, to complete a circuit that was accidentally left out of the PCB design, or a "naturally occurring" faulty trace connection on an otherwise perfectly serviceable PCB) and be done with it.
BTW, from the context of your posts, it seems to me that you're describing traces, not vias. IIRC, a via is a through-hole with no component lead soldered through it. A via's purpose is to make interconnects for traces on different layers, either top to bottom on a "two sided board" or anywhere on the layers between on a "Multi-Layer PCB" like your Classic II's.
Check for HiRes scans of your board in the NuBus Mafia collection over at Applefritter, there may be all the reference you need to fix your board there. If not, you can certainly find the end points of the trace with a continuity tester.
Those are through-hole leads and vias, correct? :?:Ok... another update.
I've scraped off the solder mask over that via that leads to C8 very delicately, and tried to solder a wire to it. bad idea - the wire wouldn't stay in place as the solder was heating up . Long story short, I ripped out the top of the via connected to C8 + by accident. Can anyone tell me where it leads, so I can manually connect it please?
EDITI've now also lost C4's negative lead...
If so, you've soldered the wrong side, pre-SMT boards, and hybrid boards like yours, of that vintage were "Wave Soldered" and any connection in a through-hole doesn't actually need the top pad unless there's a surface trace connected to it. In that case, repair the damage with a rework patch (those little pieces of wire commonly found on old boards, either coupled with an intentionally cut trace to remedy faulty PCB Design, to complete a circuit that was accidentally left out of the PCB design, or a "naturally occurring" faulty trace connection on an otherwise perfectly serviceable PCB) and be done with it.
BTW, from the context of your posts, it seems to me that you're describing traces, not vias. IIRC, a via is a through-hole with no component lead soldered through it. A via's purpose is to make interconnects for traces on different layers, either top to bottom on a "two sided board" or anywhere on the layers between on a "Multi-Layer PCB" like your Classic II's.
Check for HiRes scans of your board in the NuBus Mafia collection over at Applefritter, there may be all the reference you need to fix your board there. If not, you can certainly find the end points of the trace with a continuity tester.
I do know what a via is. I'm saying, I accidentally ripped off the top of one that the trace from the cap lead went to - i now have NOTHING to solder to. the ... I think the word is "annulus" of the via is GONE. Mars' assessment that I am up a certain creek without a certain propulsion device is almost certainly correct - I screwed myself
A rework patch implies that I can actually solder to something. I can't. There is nothing to solder to - the solder won't take to what's left of the via (which is, in this case, not a through-hole - it is a blind via) ... and in fact the solder wasn't taking to ANYTHING.
(I apologise for being defensive, but I'm kinda bummed at how epicly I've failed here.)
I doubt my continuity tester will tell me much. But, the hires scans sound good, I'll have a look. Thanks.
suggest a price ... seriously, I don't have money out the ears but I am looking to get this machine working. If your board doesn't work I'll just strip the analogue board down to parts and keep the CRT as a spare for my Mac 128k once I figure out how to get it repaired.
( p.s. could you possibly throw in the saucer-with-slot shaped mic that comes with the classic II, if you have it? :\ )
nah, you could just practically reverse engineer the entire machine with a continuity tester, it wont be much help
also back the heat off your iron, it seems to be way too hot if your loosing pads like crazy and the solder wont stick to anything but, and use plenty of flux
NoPro, comrade, I understand, been there, done that and I've got the burn scars to prove it, but the ex got the T-Shirt in the settlement. :-/I do know what a via is. I'm saying, I accidentally ripped off the top of one that the trace from the cap lead went to - i now have NOTHING to solder to. the ... I think the word is "annulus" of the via is GONE. Mars' assessment that I am up a certain creek without a certain propulsion device is almost certainly correct - I screwed myself
A rework patch implies that I can actually solder to something. I can't. There is nothing to solder to - the solder won't take to what's left of the via (which is, in this case, not a through-hole - it is a blind via) ... and in fact the solder wasn't taking to ANYTHING.
(I apologise for being defensive, but I'm kinda bummed at how epicly I've failed here.)
BTW, the only stupid question, here in the 68kMLA, is the one that doesn't get asked!
Whatever . . . how about creating a "new annulus" (albeit a "solid" one) by using just the right gauge wire to almost fill the hole, providing a path for the solder to connect to the buried layer, sort of the way a plumber "sweats" a copper pipe <-> fitting connection?
De nada, comrade!
I love your avatar too, but the designer missed the boat, IMHO. If the colors were a tad brighter, solid, and ordered correctly to match the Rainbow Apple Logo, it'd be absolutely PERFECT!
The saucer that sticks to the classic on the side? I don't have that... The soonest I could get it to you is this weekend. Hey someone here name a price for what you think the Lobo is worth, I have no idea.
As with many civilised places on the tubes, I'm led to believe.BTW, the only stupid question, here in the 68kMLA, is the one that doesn't get asked!I do know what a via is. I'm saying, I accidentally ripped off the top of one that the trace from the cap lead went to - i now have NOTHING to solder to. the ... I think the word is "annulus" of the via is GONE. Mars' assessment that I am up a certain creek without a certain propulsion device is almost certainly correct - I screwed myself
Way ahead of you, and in many ways behind. I attempted this already. As I said, the solder won't take to the board. I know it's not a problem with my technique as I assembled a multimeter a few days ago without incident.
I agree. I'd do it myself, but frankly I'm not a graphic designer. I'm a photographer and a sucker for old tech.
However, the Rainbow Apple colours would be totally pimpin'.
First, find out how much it would cost to send the logic board to Sydney. Then, based on that price, figure in how much the Classic II is worth in today's money. Then come to a median for what seems reasonable for your compensation. That would give you a rough estimate as to how much it would cost. International deliveries will always be pretty expensive, but if you stick to shipping it out via the post office than FedEx or UPS, you will find that it is cheaper.
Midnight Commando: Please tell me you have indeed burned your fingers in the attempt to solder/desolder your project. If so, you have earned our respect as a hardware hacker. In a way, it is one way to be considered one of the elite. Don't give up, though. Your experience will get you somewhere.
Until new pictures of your current Logic Board are posted, it's hard to say if whether you're flogging a dead horse or if it can in fact be completely revived. You've certainly got a lot of cleaning up to do along with some patching up of what has been damaged. Don't feel bad about having the pads lifting off the board and breaking; its happened to me too. The best thing to do is to visually follow the paths of where the traces go. This will get you to the place where you'll need to create a new bypass. I, too, agree that using a small gauge wire (about 24 AWG or lower) will give you the benefit for not using so much heat.
I've done my share of recap jobs in the past. And I'd be lying if I said I didn't make any mistakes. The thing I've learned is to take your own sweet time; you can't rush art.
Btw, as a hint, I've found that almost all boards created by Apple since the Macintosh II are in fact surface mount components (SMTs). Very rarely have I found a genuine Apple product that used components that had to be soldered through the holes on a printed circuit board (PCB).
73s de Phreakout. :rambo:
As someone who does indeed burn his fingers quite a bit soldering, maybe I am a bit of a snob, but I think the respect comes only when you manage to solder your finger to something, Its much more painful then just the heat
and after time the heat and burns do not bother you much, if at all ... just the other night i was soldering a wire, and the insulation had melted off under my fingers
I burned myself once AFAIR (Remember), got a ginormous blister. The other times I touched my nail but it does not hurt.
Consider it done, comrade! :approve: The only question is whether you want it with the pirate eye-patch or without! [}I agree. I'd do it myself, but frankly I'm not a graphic designer. I'm a photographer and a sucker for old tech.
However, the Rainbow Apple colours would be totally pimpin'.
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Darn! I am in the process of doing it!
Let's see who can do it better
Let's see who can do it better
I hear Classic IIs aren't that expensive today, what with all the iMacs that are out
A very long time ago, when I was repairing a PowerBook 1xx (I don't remember the /exact/ one) for a friend (battery issues) I actually gave myself significant burns across my hand while I was working - I didn't know at the time that the cells got so hot!
And also, I have burned my fingers, yes - electrolytic caps make WONDERFUL heatsinks!
I'll post a high-res photo of the area with the two stripped pads/tracks when I get back from breakfast. Hopefully that will be adequate to determine what's going on
I'll probably try to get that logic board off Mars anyway - and if I get this one fixed, I can use it as a spare, or give it to someone who has a screwed Classic II This is ending up to be more trouble than I anticipated. But never will it be more trouble than it's worth
OK Lets say 20$ +Shipping? Feel free to haggle. And lower it.
$20 AU wouldn't be soooo bad... but I'd still probably see the whole machine for that ...
what's your US exchange rate like at the moment? I think it's something like 0.75? How does $15AU take your fancy (probably ends up being just over $10US, possibly closer to $11) and I'll also cover shipping?
I'm also going to have to feed trag $15US or so to send me a set of replacement caps - thankfully I already have the values
what's your US exchange rate like at the moment? I think it's something like 0.75? How does $15AU take your fancy (probably ends up being just over $10US, possibly closer to $11) and I'll also cover shipping?
I'm also going to have to feed trag $15US or so to send me a set of replacement caps - thankfully I already have the values
Just before I post the photo, a thought a friend of mine had about SimasiMac:
It made my day
Here you go - a high-resolution photograph of the current state of the board... (it's 7MB, so be warned fairly)
And a preview
If you lift of a pad you need to super glue it back down on the board, let it dry. If the track is ripped use some flux and solder it back to the other side. You will need a meter to check to see if the fix worked.
When reworking capacitors revome the old part, clean with 100% alcohol any goo left over, remove the old solder with an iron and copper braid, re-tin with solder, then put new capacitors on. I suggest you use the old rosin-lead solder and not the new lead free junk (less cold solder joints).
When reworking capacitors revome the old part, clean with 100% alcohol any goo left over, remove the old solder with an iron and copper braid, re-tin with solder, then put new capacitors on. I suggest you use the old rosin-lead solder and not the new lead free junk (less cold solder joints).
I hear ya. I assembled a DMM with solder that was 99.3% Tin, and 0.7% Copper ... very hard to work! Thankfully it wasn't TOO much of an adventure.
RoHS - making electronics hobbyists' lives hell since ... when did the EU sign up to that garbage?