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Found 16 results

  1. Think the Macintosh 128K, 512K & Plus motherboards don't need a recap? Time to Think Different. It's been 35+ years since the debut of the 128K & 512K, folks. Fluid-filled capacitors don't have eternal life. Properly chosen solid Tantalum, on the other hand, will last the life of the board. My video below shows recapping of the keyboard too. PLEASE watch on YouTube so you can expand the text description under the video, as it contains Mouser Carts and important info, especially for you Mac Plus owners. https://youtu.be/vz2NGF5Vuao
  2. Hi all, I'm trying to get a 512k (intl analog board) up and running again, and I think I've tracked the problem down to the power supply. The initial presentation was a dead mac (no video or chime, no HT as far as I could tell) with a rapid clicking/chirping when power was applied. I measured the 12V supply to be peaking around 4V, and 5V to be around 1.2V. I started off by recapping all the electrolytics, with no change. I also followed the suggestions in the Dead Mac Scrolls (rectifier replacement, video cable continuity) to no avail. After some poking around on the 2
  3. Hi! New here Was going to post this here first, but as my activation email didn't get thrue until today, I posted this already in Reddit /r/vintageMac. I came across a local ad for a Mac 512K keyboard and mouse. Reading the ad, I noticed that it actually noted "a non-working Mac 512K can also be included". This was interesting as I rarely see Macs of this vintage locally, and this was only a short distance away from me. From the photos I could see that the machine was a 120V which was interesting (living in a 220V country). Ok, I went to bought the set for less than 100$.
  4. Greetings! Long time 68K owner / user, occasional forum lurker, and recent member here. After a several year 68K hiatus, I managed to find a bit of free space and spare time to devote to this former hobby For the past 25 years I've been in possession of my father's 512K, which he purchased new in 1984 fully accessorized. After years of collecting bits and pieces, I finally realized a long-time dream of getting it online Current config / accessories as follows: Mac Plus ROMs MacSnap 548E 2MB RAM board HD20 Harddrive 2 x 800K Floppies (int / ext) Shiva
  5. Well, I'm in tears again over my own foolishness. I've been shooting a video that focuses on recapping of 400K floppy drives. I hadn't begun the actual recapping but was doing some preliminary tear-aparts and testing. I had my 400K floppy drive mechanism connected via ribbon cable to my 512K motherboard, but I had the drive mechanism pulled outside the back (with the back case off) and sitting on some plastic floppy disk cases. I had a single jumper wire with alligator clips at either end connected to the metal chassis of the Mac and to the metal chassis of the floppy drive. All was going
  6. It’s been long in coming but I finally kicked it out today. Yes, even your working order Mac 128K through the Plus can use a recap. A video INDEX is in the text description on YouTube to help you easily refer to different sections of this 1 hour video. Even if you aren't interested in a recap, check out the bad Flyback segment where it lights up in the dark!
  7. Hey guys, I just have a simple question to ask. I have a Macintosh 128k with what I think to be a 512k upgrade board. It even says 512k on a little sticker on the board. However, it is missing the Roms to it. It just displays a checkerboard. My question to you guys is, what roms should I purchase? 512k roms or 128k roms. Thanks again, any help is welcome.
  8. I had a good look through the “Sad Mac” error codes web page and couldn’t decipher the code. On startup every time I get a 01C000 code and I have no drive drive activity despite having a good boot disk (verified on another machine) if anyone can tell me what this means that would be great! Thanks.
  9. Yes, even the Macintosh 128k/512k KEYBOARD needs to be recapped: But does it really need to be 63V? Here's the keyboard schematic, with the 1uF cap showing in the upper right area nearest U2: And U2 is the 74LS123 shown here: Sure, I can find a Mouser $3.23 replacement, but why is the stock cap rated at 63V? Is it because people might be stupid and connect the keyboard to a phone jack, or is there some other reason? The reason I even wonder about this is because if lower voltage 1uF caps can
  10. Hey all, I bought a pallet of old macs from a warehouse sale, and one of the machines was an old 512k with some weird upgrades. It looks like someone added more RAM and a SCSI port (which was threaded through the external floppy port hole). I can’t tell if this is one upgrade or two. I’d like to get this little machine working again, but it looks like whoever upgraded this machine made some strange changes to the motherboard, so I’m not sure if they can be undone. Is anyone familiar with these upgrades? The RAM upgrade is called Mac’s
  11. I thought about putting this in peripherals, but it seemed better here since this type of floppy drive mechanism is exclusive to the 128 and 512K Mac. It is also found inside the guts of M1030 400K external floppy drives. As posted earlier (see links in this post), I have an early 128K Mac that is now fully functioning apart from the fact that it came to me with a non-working floppy drive. After a good bit of puzzling, I discovered that it was an original Sony OA-D34V 400K floppy drive (originally shipped with a stepper motor bearing the round sticker which should work in the 128K
  12. I am having issues with my Macintosh 512k. The machine will usually boot with the checkerboard pattern shown in the pictures. Sometimes it will make a very distorted sound on boot. The issue is not with the crt as it has been tested with other boards. Occasionally the checkerboard pattern will change. I suspect the the issue is with the roms installed. I have tried cleaning the roms but this does not change the issue. I am curious if any one else has ever had a problem similar to this.
  13. So I just bought a (new to me) Macintosh 512K for $60 (USD). It came with the 512K (dur), keyboard (original), mouse (IIc mouse) and 400K external floppy drive. Oh, and a non-Apple bag to carry it all in. The computer has a small crack in the case on the top-right but I think I can eventually fix that or even replace it. It's also VERY yellowed so I got some retro-brighting to do. I will post some pictures later. The first thing I do is power it on. The seller showed a picture of it working. I don't have any software for it so all I got is the disk wi
  14. Hi All, I recently bought a 512k and It worked when powered on once after it was delivered. I unplugged it & spent a few weeks learning about the system & preparing to refurbish it. I plugged it in yesterday and there was a pfft and it started smoking. I unplugged it so no other harm was done. I've tried to look for description of a similar occurrence online, no luck. I've consulted the Dead Mac Scrolls & Macintosh Repair & Upgrade Secrets. Anyone have any ideas? Thanks
  15. Hello! I bought a Mac 512 that has a problem with the mainboard. When I got the Mac, the ROM chips (low, high) were interchanged and the MAC did not start. I changed the ROM chips and the the MAC started somtimes. Sometimes I got a sad MAC with the error 05FFFF. Sometimes I got no Image and sometime the MAC started up to the disk picture. At every start I do not get a chime. When I put in a disk the picture begins to wooble and then the MAC crashes, sometime there can be heard some sounds. I can not read a disk without crashing. What I did up to now: - Changed the ROM against a ROM from as
  16. I have a macintosh 512k and keep getting sad mac error code 024280, I have found out i need to replace the ram. I did a google search of it, but couldn't find the right ram. RAM= NEC d41256c -20
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