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  1. superjer2000

    512K Disappointment

    Got it all working - I fully disassembled and cleaned the machine, mouse, keyboard and retrobrited those parts. I recapped the analog board and changed out the components I normally do on Pre-SE analog boards (CR1, CR5, CR20, CR21, U3, Q1, Q2 and Q3), resoldered flyback, logic board connector and replaced J1 and corresponding plug. I fired it up expecting it to work on the first try and just got the repeating flup noise which I think is what the prior owner indicated was the issue. Looked at Dead Mac Scrolls and tested the 5V line on the cable between the analog board and the logic board and sure enough, no continuity. There is a 2.5A inline fuse in the wire harness that tested open. I ended up just replacing that wire (i.e. removing the fuse) and presto the machine fired up. When I was testing the machine I noticed that all keys on the keyboard worked except for the delete key. I pulled the key switch and disassembled and noted a fair bit of corrosion. I soaked it in vinegar for a couple of days (with a piece of wire separating the two plates in the switch), soaked it in distilled water with baking soda, dried it, applied some contact cleaner/lubricant and that fixed that key switch. I just tested the SCSI port and that works great as well. Only downside is not a lot of software runs within 512k but a fun project nonetheless. Note, although it is an M0001WP, it had the 110V analog board installed. It must have been swapped out at some point.
  2. superjer2000

    Quadra 950 PSU died... <cry>

    This is interesting... a number of folks, myself included had bad experiences (insuffient airflow) with the standard 60mm Noctua fan in the SE/30. This likely explains that.
  3. superjer2000

    Craigslist Mac SE, Mac SE, and Mac Plus

    @PotatoFi Did you have any issues with the RF paint on the inside of the case of the Plus or SE from retrobriting? I did a IIsi using full submersion and it ate a lot of the RF paint on the top cover. The paint on the compact Macs seems more resilient but I haven't tried it yet.
  4. superjer2000

    512K Disappointment

    It might be good to try to resolder the plug for the cable that goes to the logic board as it carries the video signal.
  5. superjer2000

    512K Disappointment

    Thanks @Crutch, that's more than I'm keen to spend. I'll just restore the analog board and live with my 512k of ram...
  6. superjer2000

    512K Disappointment

    I picked up a 512k today - I already have two other 512s but I wanted to get this one as I spotted a SCSI port at the battery location. I removed the SCSI plate and was happy to see only minor corrosion from the battery, and all confined to the battery holder. The unit does have a MacSnap SCSI but unfortunately that's it. No CPU upgrade or even a RAM upgrade. I'm not sure how useful a SCSI port will be with 512k RAM. I haven't booted the machine yet as the seller said it wouldn't start (it just clicked). The model was a M0001WP (and indicated 220V on the back) so I figured he was trying to run a 220V board here on 110V, but when I opened up the unit, it seems to have a 110V analog board so it must have been retrofitted at some point. I'll install my usual new caps, rectifiers and other upgrades and I'm sure that will get it going again.
  7. superjer2000

    3D Print Replica HD 20 SC Enclosure?

    @PotatoFi What 3d printer do you have? I've got a monoprice mini select v2 which works great but is only 12 x 12 x 10 build area. I've been looking at the new Prusa or Creality but those are around 21 cm sq x z axis which is normally enough. Your printer seems to have a bigger build area than that. Thanks!
  8. superjer2000

    Apple Monitor IIc A2M4090Z Capacitor list

    Yes - 120V model. I debated changing the filter caps anyways but decided to leave them alone. There are probably six or more pots that needed to be adjusted. I am sure a big part of it was my fault as when I cleaned the pots with the contact cleaner I moved them back and forth upsetting the prior settings. It was hard to reach a lot of them once the monitor was back together but I was able to contort my video adjustment tools to make it work.
  9. superjer2000

    Apple Monitor IIc A2M4090Z Capacitor list

    I recapped my Monitor IIc a couple of weeks ago. The other thing I did was spray some contact cleaner in the contrast pot and other pots as I was having some issues when turning the dial. When i I got it back together I had no video and needed to sort out all of the pots again but it works great now. My filter caps were film type not Rifa so I left them alone. Thst monitor was quite the beast to disassemble! i did my Apple Monitor II at the same time. Both are great displays.
  10. superjer2000

    LC575 C2/C5 Capacitor Question

    Bump... Still hoping somebody can confirm what the positive pads of C2/C5 on the above LC575 board revision connect to...
  11. When I recap a pre-SE board, I always replace EVERYTHING on my list - That list includes all electrolytic capacitors plus all of the upgrades in the repair/upgrade secrets book plus a couple of other identified failure points. While I can't say for sure, I think the total cost of the parts I bought was probably like $200 which was enough for 10 boards. After doing this a few times, I haven't had any issues with any of my recapped boards (of course, they all probably have less than 20 hours on each of them so with any luck they'll outlive me).
  12. The first post of this topic has an Excel spreadsheet with all of the caps and upgrades I used when recapping my pre-SE Macs.
  13. superjer2000

    LC575 C2/C5 Capacitor Question

    The pads in the yellow square (on the front side of the logic board) are the ones I'm referring to. They are connected to each other and to the via I have circled in the picture (front side). That via goes to the back of the board (circled in the next picture-back of the board). The via contact looks a little worse for wear - that's just from my multimeter probe. Based on the very similar color classic logic board, I think that there should be a connection between the C2/C5 + pads on the front to a resistor on the back of the board which would then connect to the chip (noted with the arrow) on the front side of the board. I'm hoping somebody can slide out their 575 board and check what that via should connect to by dragging the other probe of their multimeter across the resistors on the back of the board highlighted in the orange square. Any help on this is appreciated!! THANKS!
  14. superjer2000

    LC575 C2/C5 Capacitor Question

    Should say C2 not C20...
  15. superjer2000

    LC575 C2/C5 Capacitor Question

    I removed the caps from the logic board of the LC575 I just bought. Before soldering on new caps, I always like to check to ensure that the pads have continuity somewhere else on the board to see if I have to do any jumpering. The positive leg of C5 and C20 are connected and then C2 connects to a via that goes to the back side of the board. That via must connect to a middle layer in the board as you can't see any traces on either side. I have buzzed the pins of all nearby components and I just can't figure out what the positive side of C5 and C2 connects go (or my trace is broken). Would somebody mind using their continuity checker to see what C5/C2 should connect to?