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Found 14 results

  1. Hi everyone, I have Macintosh Plus, the screen disappears after some time and I usually just slap the side but now it doesn't work the screen Is completely blank (yes I turned the brightness to maximum amount alas nothing changes). Does somebody know how to fix it or what causes it?
  2. TimTheEnchanter

    Macintosh classic brightness issue

    Recently my friend has bought himself a Macintosh classic. It’s in amazing condition the only problem is that he decided to replace the capacitors on the digital board himself. Whilst doing this he ruined a few traces and did a terrible job of soldering. After he had done this and run into some issues he gave it to me as he no longer wanted to keep it. I would say this computer looks “out of the box” new but for the issue that the screen wasn’t working. I took it apart and fixed most of the issues that I found apparent and tried again and as luck would have it, it now chimes and displays a screen! But there’s one issue... the screen flickers horribly! Not as in loosing connection but the brightness is all over the place! I’ve never messed with one of these and have no idea where to start my search for issues. I’ve already looked at all the solder connections on both boards and reflowed that of witch I found needed to be taken care of. All of me research pointed me to this site so I come here hoping I get some help! I’ve attached a video of the screen to show you exactly what the screen is doing. Feel free to ask questions as I am really looking to get some help. Thanks! 489EA673-D066-40FC-A9E9-8456F6F69BC8.MOV
  3. Hello all - For the past few days I've been wrestling with this Macintosh Plus that has some serious analog board issues. When turned on, the system does not chime - it is completely silent. It appears to be dead, however, if the brightness is cranked up nearly to the max, a very distorted picture can be seen. It appears to be a partial vertical collapse, but on the top of the screen rather than in the middle. I've never seen a Mac exhibit this symptom before and am stumped as to where it is originating from. The small bit of vertical picture left also occasionally changes, as can be seen in one of the photos. Of note is the fact that measuring voltages through the mouse and external floppy ports, I get noticeably weak voltage - approximately 3 volts on the +5 volt rail, 8 volts on the +12 volt rail, et cetera. The floppy drive is also completely non-functional. I'm not sure if the problem here lies with the power supply or something in the video circuit. I've replaced most of the capacitors except for a few which I did not have replacements for, and those I verified with my meter to be within spec. (I did not replace C1, but it measured close enough to 3.9 uF that it seems to be fine). I've reflowed the yoke connector J1, the logic board power/video connector, and the flyback transformer solder joints and made sure they all have proper continuity. I've also tested the logic board with another known good Plus, and it boots and functions as normal. If anyone could point me in the right direction in fixing this issue, I would be extremely appreciative. Regards, CJ
  4. Greetings, I'm new to all this but I just found a Macintosh Plus 1Mb in the dumpster at work. Took it home, blew the dust out, looked at the capacitors and none of them were bulging or busted. That was fine, everything looked almost perfect aside from the usual yellowing etc. So then I thought I'd see if it would power up. It only took a second but the screen never lit up (despite making that high pitched squealing that CRT's usually make); in that same instant the Flyback transformer ruptured (pictured) and let out a puff of smoke. I safely discharged the tube and put it away because I'm unsure how to proceed. I've searched here on the forms before posting this to get other opinions, it looks like there's a few options for FBTs because the ones alluded to in the '90s repair book aren't easy to find anymore. Since this happened, do you think the tube is still good? Should I replace that as well or just the caps on the analog board / the AB itself? If parts are swappable with later macs that's fine, I don't plan on using the actual logic board if that's not compatible. I'd like to do the BeagleBone X11 display project on this one to then emulate retro systems. Any advice is greatly appreciated. Thanks~
  5. jupo

    SE/30s with dim CRTs

    Hey, all. I have four SE/30s out of a large stash that have been in storage (long story) for years. I started going through them this week and I think all four logic boards are generally in working order after a thorough cleaning (apart from obviously needing recapped). But what seems to be new is that all four of them have terribly dim screens. I tried playing with the brightness pot on the analog board on one of them and although it did raise the brightness, it also became blurry and introduced diagonal lines unless I turn the front brightness knob back down to about half to 1/3 as bright as the Plus or SE sitting next to it. I've been digging around but haven't seen any clear answers. I don't see visible issues with the capacitors on the analog boards, but is this where I should start anyway? Or the flyback? Or is scavenging a tube maybe from one of the SE's my only option? Appreciate any and all advice...
  6. mjhagen

    SE/30 CRT issues

    Hi all, I received a dead SE/30 that I’m trying to bring back to live. When I first switched it on it started without a chime and on screen was just a vertical line. To fix the audio I did a manual cleaning and re-cap of the logic board. For the vertical line I read that it’s probably C15, however after changing that out I ran a smoke test and I heard a loud-ish squealing sound and I switched off the power supply. To test the logic board I figured I’d try a known good AB/power supply and it booted into the flashing question mark (yay), but after 10 or so seconds the screen started to flicker, show static, then the squealing sound happened on the new AB as well and I quickly switched off the machine. I then started smelling burning (boo). On the original AB there’s a brown spot on yoke connector at the green wire, and also at the CR2 diode. Is there anyone here that can think of a clear cause of this? I thought about it being the fly back, but why would that happen immediately to a working AB? Another possibility would be the yoke connection in the CRT side, which looks a bit messy and I haven’t looked into schematics for that thing yet. Or something else on the yoke itself because that along with the LB were the same in both cases. Mingo.
  7. Hello people! I recently acquired a Mac Plus while doing a clean out of my grandfather's old factory. The keyboard and mouse were FUBAR, as they had been left under an old can of paint which leaked all over them. He said that there was also a hard drive somewhere, but we couldn't find it. I scrubbed as much old paint of this Mac as I could, and besides from a rather even coat of yellowing, it seems to be in pretty good nick. I took it home and plugged it in, and it made the start up bong and the floppy drive made noises, but the screen never fired up. I cracked open the case and besides some dust, everything seemed to be in relatively good shape. No caps were leaking, and nothing looked corroded. I also discovered that this Mac had 4Mb of RAM. Nice! I came to the realisation that this Mac had deeper problems. I noticed when I found the Mac, that it had LOTS of screen burning, which indicated to me that the CRT as a whole could have just bit the dust, or that the flyback transformer was completely screwed. Further poking around inside the machine also revealed that the CRT power connector looked like it was burned or melted. I thought while I had it open, I'd perform the cap change just in case, for longevity if I ever got this thing working. I couldn't find all the correct caps, so I used some higher volt ones, and there was one blue non-polar one that I didn't change at all. Upon firing this up after the change, it worked! I have no idea why the cap change fixed it, non of the caps seemed damaged in the slightest, I verified this when I removed them. No residue or anything! So now I have a semi working Mac, but I have 2 issues which I'm unsure of how to fix. The computer makes a REALLY REALLY high pitched squealing noise. I think this may be the flyback transformer, but I'm not sure. UPDATE: When I fired up the machine to take the photos in this post, the noise was gone! I'm unsure if it will come back, has anyone else had this problem? It's also VERY hard to insert floppies into the drive. The seem to be stuck on something, I'm not sure what though (I've made sure it's aligned correctly). Also, sometimes when I put them in, the jitter around in my hand like crazy until whatever mechanism in there stops, and I can finally insert the disk! And on top of that, the auto eject doesn't seem to be working, but I'm not that familiar with macs that boot directly from disk, as my other mac (a mac classic) is currently not working AND it has a hard drive. I also have no boot disk to test this machine further. Let me know what you guys think!
  8. Dear members This is a PDF that I obtained from the archive.org. If you are considering taking apart your compact mac please take special care of CRT safety, this is a very good, short PDF on the topic that I hope you can all enjoy while working on your mac safely. Originally from, AppleCare Service Source http://service.info.apple.com/safety/safety.html#ESD Safety.pdf Topics covered: ESD Damage Prevention Follow these guidelines to reduce the risk of electrostatic discharge (ESD) damage to equipment. ESD Prevention Rules Setting Up an ESD-Safe Workstation CRT and LCD Safety It's imperative to know and follow all CRT safety procedures listed in this section. CRT Safe Electrical Setup Precautions Discharging the Cathode Ray Tube (CRT) Removing the CRT/Video Board Establishing an Ongoing Lead to Ground Return Worn-Out CRTs LCD Safety Battery Handling A primer on battery handling and disposal. Battery Disposal Kind regards —Alex Santos
  9. ktkm

    SE/30 CRT Geometry knobs

    Hello before I die! After watching techknight’s video regarding CRT Swaps, I was intrigued how easy it looks. After much consideration I’m thinking of performing something similar with an SE/30. However, one thing the video won’t explain is how exactly the knobs work (see attached image). 1. First of all, are they safe to touch with your bare hand? 2. There are eight knobs, but which knob affects exactly what part of the screen geometry? 3. Once moved/rotated are they stable, or do they need glue of som sort to stay fixed? 4. Two of them (2 and 3 in the attached image) seem hard to reach, how are they best dealt with? Has anyone here done this successfully? Sincerely, ktkm 9_inch_crt-geometry-1.pdf
  10. Hello I thought I would come here to ask as most of you are surely more learned than I am. I have taken apart a Color Classic and would like to do a complete cleanup. I have properly discharged the CRT and the machine is in pieces right now. For now, I would I have some basic questions. Should I recap the analog board? Never done it but I have soldered in the past. Is it safe to clean the CRT and potentially the analog board. I have a can of air but potentially I was thinking of using Isopropyl Alcohol and a q-tip. Maybe the folks on this forum can understand how particular I am being about cleaning this little guy up. Others might think it's weird but love for these little show pieces goes a long way, besides it's a lot of fun. Would love to get some advice. PS, I have all the proper tools and am using an ESD mat and wrist strap. Cheers! —Alex
  11. From the album: Macintosh SE/30

  12. I've bought a Macintosh Classic computer recently, it was in a very nice condition with original keyboard and mouse, but with an issue of a chessboard-like pattern displayed on the screen all the time. At first I thought that it might be caused by capacitors leak on the logic board, but after I've cleaned the logic board in a dishwasher and than with pure alcohol, nothing happened — the pattern on display was the same. So I decided that caps are dead and need to be replaced. I've replaced all the capacitors on the logic board, but again with no result. After that I've found the information about this issue might been caused by broken capacitors on the analog board, so I've replaced a group of caps mentioned here (http://www.maccaps.com/MacCaps/Capacitor_Reference/Entries/1990/10/15_Macintosh_Classic_Analog_Board.html) total 8 caps, although they aren't all the same as in the guide, cause I have a later model (1992) I suppose. Still no result, the pattern on the screen is absolutely the same. What else could I try? Any help or ideas are much appreciated!
  13. Hi folks... I saw this interesting mod to a 1984 Mac. The CRT was swapped out for a LCD. The Mac now supports USB and some other cool features. It is running Snow Leopard. What I like best about it, is that it is a non destructive mod. If you like, you can put the original hardware back in the case and return it to normal: http://www.instructables.com/id/Upgrade-your-original-1984-Macintosh-to-run-OS-X-S/?ALLSTEPS Probably everyone but me knows about this already. This mode was done in 2010. Rather then The cube, I have been looking at the Mac mini. The mini is so small that I believe I can use some ideas from the above to install it in a dead Color Classic case with out altering anything. But I have problem. I like CRT screens, but not a big fan of LCD or LEDs. I would like to marry a Mac mini to the CRT in my dead Color Classic. Where on the web can I read up on how to do this? I would not like to re invent the wheel if someone has already drawn out a circuit diagram on how to do this. I suspect someone has taken HDMI out and built a box that would output something that a CRT can take. This probably has nothing to do with Apple computers. I am not sure where to start looking... Anyone have any information on this, or can you point me to some web sites to read? Thanks jack
  14. Cory5412

    Multi-System Workflow

    From the album: Cory's Stuff

    In the Olden Days™ I definitely used to do photo processing on one computer while I continued to faff about on the Internet with another computer. This is my PowerBook G4 (the one whose serial number I will never forget) connected to a monitor, keyboard, and mouse processing contact sheets (which I printed and that was how I browsed my photo library) while I use the #68kMLA IRC channel on system 7.1 on my Quadra 840av. I had juust gotten broadband Internet, and the notion of having multiple computers online at once, all the time, was still very foreign to me. Just as an example of how differently I compute these days -- this was when I still signed out of IRC and shut off my desktop computer whenever I was going to be away for more than an hour or so.