livingonwheels Posted August 21, 2021 Share Posted August 21, 2021 (edited) I picked up a stash today and included in the stash (in the big bag to the right) was everything you see here. There are no identifying markings on the back (like I see in most pictures). I did find a serial number (F5426R2M0001W) which leads me to believe it's a Macintosh All-in-One 512k. It turns on but there is no floppy to test it with. I can move the curser with the mouse, but it's asking for a floppy. Is this the disc I need for testing (V2)?: https://www.ebay.com/itm/174774337226?var=47395942... I know very little about vintage computers so bear with me. The seller said this specific unit with no label on the back belonged to the uncle of Steve Jobs. Ha Ha, but who knows! He seemed serious. It gives off a funny smell when I boot it up. Not a smoke or burning smell, but a smell of something like a chemical. I'm afraid to keep on too long, just in case it blows up! I have a feeling that this unit hasn't been turned on in decades so this might be normal. Perhaps it will go away if I leave it on for longer that a minute or two? And what is that unit to the right of the Mac? Is that a hard drive? I can find nothing online about it. The most important question I have is...Can I play games on this thing? I'm a collector of video game related items, not really computers. Also included, but not pictured is a Commodore 64 CIB with some master disk games (at least that's what the labels say) and a C64 floppy disc drive and also a Timex Sinclair computer (very small) with a bunch of games on cassette and random accessories. Still haven't tested those though. Bunch of related books too, but have yet to go through them. All C64 and Timex related. Edit: I've opened it just to be sure that nothing was melting. Inside is A LOT of what appears to be water or acid damage. See the pictures below. I can't seem to figure out how to remove that board for cleaning? Anyone know how to slide it out? Edited August 22, 2021 by livingonwheels Quote Link to comment Share on other sites More sharing options...
DistantStar001 Posted August 22, 2021 Share Posted August 22, 2021 (edited) See if there are any round serial ports, or a SCSI Port. If so, then what you have may have been a 512k or a 128k at one point, but has been upgraded to a Macintosh Plus. I have one just like it. No sticker on the back to identify the model. The seller told me that it was a 128k, but when I looked into it, I found that it had been upgraded. Apparently the sticker for the back case was either sold separately, or the original owner never bothered to put it on. Typically, a 512k or 128k will have an embossed badge on the back, at least identifying it as a Macintosh. As for the device on the side, I would need to see the ports on the back to be sure, but it could be an external SCSI. Edited August 22, 2021 by DistantStar001 Quote Link to comment Share on other sites More sharing options...
livingonwheels Posted August 22, 2021 Author Share Posted August 22, 2021 (edited) Thank you, check my edit above. It turns on, but I need to somehow take out that board to inspect and clean it. Can't seem to figure what is holding it in. Edit: got the board out, it's a mess. At the very least I'll clean it with alcohol and a toothbrush. Edited August 22, 2021 by livingonwheels Quote Link to comment Share on other sites More sharing options...
bluejay Posted August 22, 2021 Share Posted August 22, 2021 (edited) Jeez, is that battery damage? There’s a model number on the machine, M0001W is 512k. The floppy drive appears to be a double sided 800k drive, so it’s probably a 512Ke. No way to verify if it was owned by Jobs. Something tells me he wouldn’t have used an aftermarket hard drive with his Mac. Speaking of which, if you could take a pic of the back and the cables connected to it, it would help identify exactly what it is. Macs had no built in SCSI support until the Mac Plus, so if that is indeed an external SCSI hard drive, it probably has some aftermarket SCSI interface installed to it. I run System 4.1 on my 512Ke, but I believe it can run operating systems as new as 6.0.8. So yeah, that eBay link is the correct one. Make sure you buy one on an 800k disk. Sure, you can play games on it, but it’ll be a pain in the ass. There are hardly any really good games that run on these ancient Macs, and actually getting those games onto the Mac is a whole different story. To put it simply, you’ll need another Mac that can read PC disks and can copy 800k floppy images into double density disks. These bridge machines range from Macintosh SE FDHDs from 1987 to PowerBook G3 Wallstreets from the late 90s. Otherwise you could have someone else make the disks for you, or buy an expensive Floppy Emu that’ll easily let you load any software to it. The smell’s probably an exploded RIFA capacitor. No biggie. C64 will be easy to test and load software onto, as SD card based floppy drive emulators are cheap and common. The TS computer loads stuff via cassette, and you can download WAV files of software that you can play back on your modern computer with the cassette cable connected between the Timex Sinclair and your modern computer. Edited August 22, 2021 by bluejay Quote Link to comment Share on other sites More sharing options...
DistantStar001 Posted August 22, 2021 Share Posted August 22, 2021 (edited) From the picture of your motherboard, it's definitely a Mac Plus. It was likely a 512k once, but it's been upgraded. You can see the 8-pin round serial and 25 pin (D) SCSI ports. The 512 and 128k used 9 D styled serial ports and lacked SCSI support all together. Instead they used custom hard drives that interfaced through the 19 pin floppy connector. Edited August 22, 2021 by DistantStar001 Quote Link to comment Share on other sites More sharing options...
livingonwheels Posted August 22, 2021 Author Share Posted August 22, 2021 (edited) Check out this video. What could be causing this issue? There is no floppy in the machine, and no battery, if that makes a difference. I cleaned the motherboard of all the gunk. This issue that you see in the attached video below was there even before I did that though. I didn't notice any exploded caps, but I'll double check. Edit: I found the RIFA cap, yes it is exploded. Is it the RIFA capacitor causing this issue in the video? MOV01525.AVI Edited August 22, 2021 by livingonwheels Quote Link to comment Share on other sites More sharing options...
bluejay Posted August 22, 2021 Share Posted August 22, 2021 Huh, the thing looks like it’s rapidly switching on and off. Probably a bad power supply. Might be the RIFA cap that’s causing it, but make sure to check other capacitors too and replace them as you find bad ones. Quote Link to comment Share on other sites More sharing options...
livingonwheels Posted August 22, 2021 Author Share Posted August 22, 2021 (edited) Removed the capacitor, now waiting on the replacement from Digikey. In the meantime, does anyone know where these 2 pieces of shielding go? They fell out as I was turning the case over. Also I presume it doesn't matter which way the new capacitor is installed? Edited August 22, 2021 by livingonwheels Quote Link to comment Share on other sites More sharing options...
DistantStar001 Posted August 22, 2021 Share Posted August 22, 2021 (edited) Check the electrolytic capacitors as well. I had assumed that the rust was the result of a bad clock battery since what I could see of the analog board looked fine, but having a second look, and the power issues, tells me that there might be some leaking going on as well. I'd have to see the entire board to be sure. Console5 sells a kit with all the capacitors you'll need for about $20: https://console5.com/store/macintosh-128k-512k-plus-analog-pcb-cap-kit-630-0102-661-0462.html Also, you might consider scrubbing the corrosion off the metal frame with some vinegar, salt, and a wire brush. It's just not good to have that in contact with the boards. Edited August 22, 2021 by DistantStar001 Put the wrong link Quote Link to comment Share on other sites More sharing options...
bluejay Posted August 22, 2021 Share Posted August 22, 2021 3 hours ago, livingonwheels said: Removed the capacitor, now waiting on the replacement from Digikey. In the meantime, does anyone know where these 2 pieces of shielding go? They fell out as I was turning the case over. Also I presume it doesn't matter which way the new capacitor is installed? No clue where those metal bits go but it probably won't matter. RIFA caps are nonpolarized and can be mounted either way. Like DistantStar said, check the electrolytic caps as well. They're prone to failure too, although not nearly as much as the RIFA cap. If you're proficient at soldering you can also recap the entire analog board, as all parts are gonna fail eventually. However, do this at your own risk, as mistakes like mounting caps backwards (trust me, as stupid as that sounds, it happens) will zap your computer. 1 Quote Link to comment Share on other sites More sharing options...
livingonwheels Posted August 25, 2021 Author Share Posted August 25, 2021 (edited) I replaced that blown capacitor today. Worked fine for a few minutes, but began again to rapidly turn on and off like before. All the other caps look fine. Right before the monitor begins turning on and off, I hear a noise coming from a coil (pictured below). It's located directly below the new capacitor that I just installed, and is connected by a wire to the power cord port. As the monitor is in it's "on/off state" that coil is constantly making noise. It's labeled: 01555702058 906 8409 Coil Craft Think this might be the issue, or at least another issue besides the blown capacitor. After about 2 minutes the monitor begins to turn on and off rapidly (beeping each time). 5 minutes after first cold boot. I feel it's losing 100% power due to this defective coil (which is why the computer is also rebooting each time the monitor goes out). But I can't find a source to purchase another coil. Any help or suggestions is appreciated. Also, I wish there was a way to test the monitor without the computer attached, but there doesn't seem to be. Am I correct? The monitor won't turn on without the computer board attached. Edited August 25, 2021 by livingonwheels Quote Link to comment Share on other sites More sharing options...
livingonwheels Posted August 26, 2021 Author Share Posted August 26, 2021 As an update, I've been advised to change the 2 other RIFA foil capacitors before proceeding further. I ordered the complete capacitor kit from Console5 as recommended by DistantStar001. Had to order a couple more loose caps to go with the kit, for Console5 responded to my inquiry with the following: "If you were to purchase the full kit, please add on the 4700pF safety caps too as they aren't included with the kit. Not all Macs have RIFAs for Y caps". Quote Link to comment Share on other sites More sharing options...
bluejay Posted August 27, 2021 Share Posted August 27, 2021 Odd that it doesn’t power up at all without the computer board; I thought the analog board was on the same board as the power supply so it would at least power up the monitor in some way. Not that it would be helpful though, as it would obviously display no picture if nothing is connected to it. Quote Link to comment Share on other sites More sharing options...
CatPix Posted August 27, 2021 Share Posted August 27, 2021 (edited) I know that for Mac Plus 1Mb, there is an issue with broken solder joints, but it's only for the CRT, not the motherboard. Still, given the acid damage from the battery (is the battery in a holder on your model or on the PCB? if it's on the PCB, remove it immediately) you might have broken solder joints. I suggest you to reflow all solder joints on the path to AC to the transformer, and also the one for the CRT : https://macgui.com/news/article.php?t=511 This might not solve your current issue but it will save you from the hassle of solving it later. And if the Mac doesn't interest you, it's always a plus for you to be able to say that it was serviced and ready to work Edited August 27, 2021 by CatPix 1 Quote Link to comment Share on other sites More sharing options...
livingonwheels Posted August 30, 2021 Author Share Posted August 30, 2021 (edited) I replaced 2 more leaky capacitors today (2 more RIFA caps). Had it running great for about an hour. But I must say, when I first turned it on after replacing those caps, it did not boot up immediately. It turned on/off like before but much faster. After about a minute it came to life and didn't happen again. Suddenly it stopped. Now the screen is not on, and the computer will not boot. Loud noise suddenly coming from the floppy drive of all places (spinning?), noise stops when drive is disconnected, but still won't boot. No "beep" noise. Flyback making crackling noise during this, but appears to be working, could be because it's trying to boot but can't due to the drive causing some sort of malfunction. Stops crackling considerably when drive disconnected. Reflowed solder joints too with no change. Changed a few more caps for the heck of it. I'm not one to give up but I think I've gone as far as my skills allow. Might have to move on to another project. If anyone in Massachusetts (I'm located in Salem) wants to give it a shot, I'll pay for your service. Might be too heavy to ship to other states in the US, but might consider it if you think you'll be successful. I don't like walking away from this. Edited August 30, 2021 by livingonwheels Quote Link to comment Share on other sites More sharing options...
Keatah Posted August 30, 2021 Share Posted August 30, 2021 To properly fix this.. Any area where there's corrosion needs attention. Part removed, examined, tested.. The PCB should be cleaned and have traces repaired/replaced. And there's that blue capacitor which is also visibly bad. Lots of tedious time-consuming work, but not hard. 1 Quote Link to comment Share on other sites More sharing options...
livingonwheels Posted August 31, 2021 Author Share Posted August 31, 2021 I just replaced every capacitor on the power board, unfortunately the issues remain. The floppy drive constantly spins, while the flyback crackles. I've attached a video below for those curious. You might have to raise your volume to hear the drive spinning. I disconnect the drive halfway through, then reconnected it. The monitor tube does not turn on, the computer does not beep when you flip the on/off switch. The monitor will not turn on normally without a working computer anyway, so I think a chip has blown on the computer board. Which is why the monitor refuses to start and the floppy drive spins constantly. Ran great for 1 hour, then kaput. I'll inspect the computer board for any obvious damage, but that all I can do at this point. Video: MOV01557.AVI Quote Link to comment Share on other sites More sharing options...
livingonwheels Posted September 4, 2021 Author Share Posted September 4, 2021 The issue was found. It was a small chip (4N35) located at U3 on the analog board. As soon as I replaced it, the unit came to life. 3 Quote Link to comment Share on other sites More sharing options...
bluejay Posted September 5, 2021 Share Posted September 5, 2021 Congrats! Have fun (although I’m not sure how much fun you’d have with it; these Macs aren’t really that fun). Quote Link to comment Share on other sites More sharing options...
livingonwheels Posted September 5, 2021 Author Share Posted September 5, 2021 (edited) I'm now working on the external hard drive that was included. Plugged it in and a couple of the RIFA capacitors popped. The two 4700uf capacitors are the same as the ones I replaced in the Mac so I can find them on Console5, but the other two I have no idea what capacitor would be compatible. Does anyone know? Pictured below, marked 240v on the side and 0.068uf X on the top: Edited September 5, 2021 by livingonwheels 2 Quote Link to comment Share on other sites More sharing options...
Pokeypy Posted September 5, 2021 Share Posted September 5, 2021 On 8/22/2021 at 7:10 AM, livingonwheels said: Check out this video. When you turned it on, I expected it to explode. Quote Link to comment Share on other sites More sharing options...
CatPix Posted September 5, 2021 Share Posted September 5, 2021 (edited) 5 hours ago, livingonwheels said: I'm now working on the external hard drive that was included. Plugged it in and a couple of the RIFA capacitors popped. The two 4700uf capacitors are the same as the ones I replaced in the Mac so I can find them on Console5, but the other two I have no idea what capacitor would be compatible. Does anyone know? Pictured below, marked 240v on the side and 0.068uf X on the top: Lazy answer : they are filtering caps, you can just remove them. Their role is to absorb parasites from the power supply, but it's minimal and really, for vintage stuff that will certainly not run 24/7 and compared to modern sources of RF pollution you aren't required to replace them. Less lazy : any 0.068uF cap marqued as X2 (able to take AC current. X1 also exist but are rated for up to 5000V spike which is not something you'll need here) will do. If you're in the USA, a 250V replacement will do. If you're in Europe, look for 400V ones. For the sake of it, I took the cheapest ones from eBay for my Thomson computer and monitor and both have been since left working for 8 hours and more for vintage/retro expositions... Edited September 5, 2021 by CatPix 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.