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shadedream

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  1. shadedream

    Re-capping IIsi problems....

    Well... some good news and some bad news... I made a poor decision and learned a lesson about trying to re-flow very small pins gently with a soldering iron. I will not be fixing that IIsi any time soon, unfortunately. On the other hand, I re-capped the other IIsi, which was the one in worse shape of the two as far as cap goo goes, flawlessly and it's up and running. https://imgur.com/a/iSla5SN I appreciate everyone's help with troubleshooting the first one anyway. I'll worry about getting back to it when I'm a bit more experience with dealing with smaller pinned surface mounts.
  2. shadedream

    Re-capping IIsi problems....

    I hadn't plugged in speakers externally, I'll give that a try. It does click quietly when the board powers up.
  3. shadedream

    Re-capping IIsi problems....

    Yep the PSU is recapped and working, tested with another working PSU also. I turns on, HD gets power, soft power works, but no sound and just a gray (or tinted gray) screen. I've re-done and continuity tested the caps more times than I can count now (went through three sets, just in case) and nothing has changed so I'm pretty sure it's not the caps at this point. My planned next steps are look into the vias as @trag mentioned as well as re-examine all the chip contacts and potentially re-flow some/all of them.
  4. shadedream

    Re-capping IIsi problems....

    Attaching a photo of the board currently if that helps. There are two pads that lifted or partially lifted, so I've scraped a bit off the connected traces and soldered them to the traces (hence why they're crooked). They're at C5 and C31. I also noticed a couple of stray black bristles from the brush I was scrubbing the board with on there currently, so disregard those. If a closer view of any component or area would be helpful, let me know and I can take them.
  5. shadedream

    Re-capping IIsi problems....

    Clarification, I do a lot of through hole soldering work, so I might be running my temp a bit high for surface mounts.
  6. shadedream

    Re-capping IIsi problems....

    I recently recapped the PSU and tested it working in another system. I've also tested that system's PSU in this one with the same results, so I don't think it's the PSU. The board wasn't heavily contaminated with cap goo fortunately. No idea how to test the Egret chip though (or which it is). Would a ROM Issue be likely if the system was working fine before recap?
  7. shadedream

    Re-capping IIsi problems....

    Yep, used hot air to remove old caps, small tip, heat directed on caps with low pressure. The hot air rework was at 350c. I used my iron to solder the surface mount tants, ~370c on that. Through-hole soldering work so I might be running a bit high on that. I've continuity tested the caps solder joints to points on the board multiple times and things seem to be connected well. I even replaced the caps with a new set. Same result. FWIW It sound like I was similar to your experience, in that on my first boot, it chimed and worked... and then went down hill from there.
  8. shadedream

    Re-capping IIsi problems....

    Well I've removed the caps, given the pads a good clean fluxed it all back up and soldered caps back on and given it a clean. I've already done this before and nothing changed, but we'll see how it goes, it's in the oven drying for a few hours now. Is it possible a heat gun could have damaged something else on board near the caps while using one to remove the caps? I wouldn't think so but feeling a bit at a loss at this point. I have another IIsi in need of a recap but I'm hesitant to get started on it until I know where I've gone wrong with this one...
  9. shadedream

    Re-capping IIsi problems....

    I do have a multimeter but it doesn't have a specific mode for testing capacitors.... how do I go about testing them correctly? Do they need to be removed from the board or can I test them inline?
  10. shadedream

    Re-capping IIsi problems....

    No problem. I can take photos of the board a bit later if that will help. For the most part the screen is just normal gray. Once in a while when powering on it takes a yellow hue. I also forgot to mention, I already successfully re-capped the power supply, so I'm quite confident it's not related to that. I've tested another one in it just in case. I've also removed it's RAM to just use onboard as well, just in case.
  11. shadedream

    Re-capping IIsi problems....

    I didn't see any notable corrosion on legs or traces but I have thoroughly cleaned the board and cleaned the pads before putting the new caps on. There really wasn't much cap goo on this board (I have another to do which is worse).
  12. I gave in to the inevitable, ordered a bunch of caps and have started learning to re-cap these old boards and clean them up. Unfortunately this board has not been a success. It was... mostly working... before re-capping, I've re-capped the board using the recap-a-mac references, have double/triple checked cap polarity, continuity tested cap connections etc. Currently it turns on, soft boot works fine, hard drive powers up, but no boot process begins and I have no startup chime. It just sits on a gray screen which is occasionally yellow tinted. Caps were removed with a hot air rework station w/ small tip and low air pressure (so I didn't end up blowing other small components off) and replaced with tantalum equivalents. Any thoughts?
  13. shadedream

    Kensington Mouse-in-a-Box (ADB) on Mac OS 7.6.1?

    What's not working? I cant see why it wouldn't work. If it's not working entirely I'd try to confirm it's actually working at all on another machine if you can.
  14. shadedream

    Color Classic video issues

    Yeah... thats kind of what I'd feared. I'd already sent Uniserver an e-mail about the caps to get an idea assuming that was the issue before the brightness flickering started. Will need to get around to making a tool to discharge the CRT so I can get the analog board out and get the money together to ship it off it seems. Elfen, have a link to these adjustment specs? not familiar with them. Fortunately when the display pops out of it's distorted mode it's brightness and black levels are correct, though Im sure I'll probably have to do some adjusting. I did get some adjustment tools just recently to troubleshoot it, so good to go there...
  15. shadedream

    Color Classic video issues

    So I've been having some video issues with my color classic and I'm trying to track down the exact cause of the problem. When I acquired the machine a ways back everything was fine. It started with some distortion at the top and bottom corners and the display being overly bright and washed out (camera on phone adjusted for the brightness so it's not as washed out in the photo as it appears). More recently I started noticing some brightness flickering going along with it. In attempting to record a video of the flickering today, the display very briefly blanked/dimmed and all of the distortion / over-brightness was gone. The flickering remained and eventually it happened again and popped back to the distorted video. The distortion is also worse than the above photo now. Video of it in both states (didn't catch it switching): https://www.youtube.com/watch?v=O_8bPka1sYM My assumption is caps on the A/B but I don't know for sure. I have tested two different logic boards (both Performa 575 boards) in it and nothing changed. Thoughts?
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