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  1. Oh, I should add that I don't own a multimeter that measures capacitance, sorry.
  2. Thank you for this great information! The labels on most of the caps were gone when I got the board. My best information is here: viewtopic.php?f=9&t=17724, and unfortunately, I don't have a label for C1 or C2. Your list provides a lot more than I had before, however. I didn't replace the caps, but I'm sure it's in the future. Once the machine dies, I will re-cap it if all the values are known by then. Please feel free to use my photos. To be clear, my machine is a U.S.-spec original Color Classic with a LC 550 board inside. So my photos are of an LC 550. To the best of my knowledg
  3. Apologies for bringing back a dead thread, but I have an update. It turns out that I was getting audio with headphones/speakers attached, but nothing through the internal speaker. My solution was to leave a set of speakers attached. To avoid wasting electricity, I left them unplugged when the CC was off, adding a small annoyance of needing them plugged in and dedicated to this purpose. Anyway, turns out that the best solution was to leave the machine off for a few months. Turned it on yesterday, heard the chime, and did a double take because I was standing between the speakers and the CC--
  4. I spoke too soon--just needed to reseat the ROM chips. And now the co-processor works! So the washing solved one problem but not the audio issue. I'm going to spend some time with the pinouts of the audio jacks to see what, if anything, needs to be shorted.
  5. Thanks for the suggestions, and those will be my next steps once I get back online. Unfortunately, I have taken a step backwards; after the washing I now have a non-booting 550 logic board. The original CC board still boots normally, but using the 550 logic board (PRAM battery installed or not, RAM installed or not, VRAM installed or not) leads to the power light turning on and the hard drive spinning up but nothing else.
  6. Can anyone point me to the capacitor values for the 550/CC2 logic board? They aren't listed in the wiki. I'd settle for a high-resolution picture of the logic board allowing me to see the cap labels (couldn't find that either). The labels have come off of all of mine except for a few. Here's what little information I have: C1 - ? C2 - ? C3 - ? C4 - is this a cap? it's tiny C5 - ? C6 - 47 μF 16 V C7 - same as c4 C8 - same as c4 C9 - 10 μF 16 V C10 - open, no component C11 - ? C12 - ? C13 - ? Any leads are appreciated.
  7. Is it possible (through the use of some type of adapter or card combo) to have both the LC PDS IIe card installed and be able to use ethernet? I'm not talking about giving the IIe environment access to ethernet; rather, can you have both cards installed for the convenience of using either without pulling the logic board and doing a swap?
  8. Thanks, Dennis, for your interest and help. I know a little bit about circuits and hardware from a decade of tinkering, but I have no textbook training. Basically, every time something goes on one of my old machines, I learn something new about electronics. I did use a pair of working headphones and checked all the combinations you list. When I have time I'll see if I have some donor headphones I can cut. However, the fact that none of the headphone jack pins conduct to each other means that the sound should work without the port installed at all, right? Living in Orlando, I am fort
  9. Here we go- No plug inserted Headphones/Audio Out - No pins are connected. Pin 1 conducts to the thread (ground?) on the jack. Mic/Audio In - 3 connects to 4 - 5 connects to 6 With plug inserted Headphones/Audio Out - 1 connects to 2 - 1 connects to 4 - 2 connects to 4 Mic/Audio In - 1 connects to 2 - 1 connects to 4 - 2 connects to 4 - 5 connects to 6 Disclaimer: My heavily corroded parts could be faulty. Conclusions: It does appear that an open speaker jack switch = no plug inserted. The connected pins on the line in shouldn't make a difference
  10. I should have added that I did try the board without the mic and headphone ports installed--no audio. Assuming I cleaned it up properly, does this mean that I've ruled out the bad audio ports?
  11. My Color Classic saga continues. An LC 550 logic board brought my CC up to "CC II" status. It's so much faster! And so much RAM! All is well save for two problems: - No audio on the internal speaker or headphones (sound works fine with original CC logic board) - It won't boot with the 68882 FPU installed (FPU is a 33 MHz; again, works fine in original CC logic board) The logic board was in bad shape, and I was expecting hiccups. Note the condition of the SCSI, mic and speaker ports (SCSI works fine): I'm guessing it's moisture-based corrosion? Also here's the bottom... normal
  12. The epoxy fix is good news. Epoxy I can do. Are you talking about the yellow epoxy on the bottom (the PCB side around the pins), or at the top, where there doesn't seem to be any epoxy: Or am I cementing it around the base on the outside? This cap thing is too bad. I like tinkering with it, but when it's wholesale component failure at 100 solder points, it's discouraging. I'll recap it eventually. And I thought my SE- and SE/30-style problems were over with a computer 6-years newer...
  13. I hope its okay that I start a new thread for this... it's the same machine as my prior post (Color Classic) but new symptoms. History: A while back I was having a degauss problem (http://68kmla.org/forums/viewtopic.php?f=7&t=16895) that has cleared up ( ). I've been having flyback transformer issues as well (a whine), but those also are better than they were after I removed and re-soldered the flyback. There is still the occasional whine. I'm now more concerned with a flicker/brightness fluctuation on the CC monitor (happens for ~3 seconds every 5 minutes or so). I had thought t
  14. Update: I'm also having some pretty bad brightness fluctuations on the monitor.
  15. Well I finally opened it up this week, and as expected, everything was connected properly. Still have the same problem after putting it back together. The haze isn't too bad, actually, but I'm concerned that the machine is on its deathbed... I have other symptoms. It's apparently common (?) that the CC won't boot after it's been unplugged for a day or two. It has to sit with the power on for a few hours before it will boot. If I don't give it the full time, it may spin up, but it doesn't chime. It also still has the high-pitched whine. On its first successful boot up today, it restarted m
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