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cfriberg

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  1. It's been recommended to replace DP3, DP4 diodes which I am ordering. They look fine except the solder joints look burnt. What I can't find is DP8. It's a little diode maybe similar to DP3. I can't tell because it burned up. The 1st picture is just my board model. The 2nd shows DP8 under that blue cap. What is this called, so I can order a new one? Thanks for your help!!
  2. Maybe we can help each other out. I have the same project ahead of me and I've done the logic board already. Yes, I believe Y is for filter and these can be rounded up to the nearest capacitance and voltage. The footprints need to be the same or very close, though. Also, you can start with just the electrolytic capacitors. I'm not sure if your list is only the electrolytic capacitors. Where did you get the list you have there? Did you just read the caps off the board?
  3. cfriberg

    Classic II - No sound. And what about networking ?

    I had the same sound problem and recapping it solved the sound problem. Pretty much no matter what it's gonna need to be recapped and it is well worth it! If you are desperate for sound you can plug in headphones.
  4. That's fine. You can always meet or exceed the voltage and capacitor ratings. No problem! So if it calls for 47uf@25v you could do 100 or 150 at 25 or 50, etc. Just try to get a picture or dimension of the capacitor when you order it so it looks the same and will install the same. You can fudge this too if you are clever (as long as it connects somehow to positive and negative). The most important thing is making sure you install it with the positive and negative side the same as the old one!!
  5. cfriberg

    Weird noises and no display - Classic & Classic II

    Be gentle and controlled but firm with every step of the repair. Disconnect and remove the logic board. Remove all the ROM chips and RAM boards. Look up ROM chip pullers on the net and just make them yourself with a pair of old tweezers to remove the ROM chips. They are stubborn and have fragile pins. Keeping track of the order and orientation they go in. REMOVE THE BATTERY like technight said. Order a new one on amazon.com, super cheap. Coat the board in alcohol and gently scrub with a toothbrush. Stick it in the dishwasher and do a "short rinse" cycle on it. Dry it as best you can and let it set out to dry while you wait for that new battery to arrive. Reinstall all the ROM and RAM and new battery and plug it all back in and try and boot it up. If it works, Hooray! Then get some new tantalum capacitors (little yellow rectangle guys) on digikey.com and match or exceed the voltage and capacitance ratings. The smaller caps are "package/case/manufacterer" size A and the bigger ones are size C. I used two soldering irons at the same time to patiently remove both capacitor solder points at the same time. Then clean the solder pads with alcohol on qtips and solder new capacitors on with the positive and negative like they look on the bottom side of the board (positive is the black strip side of capacitor I think). I did like two or three capacitors at a time and plugged it all back in to make sure it's still working in case you mess up you don't have to go back and recheck every single capacitor.
  6. cfriberg

    smoking yoke

    Well, I tried a bunch of things and I think it is out of my scope of comfort. I feel like I'm repairing a TV more than a Mac. I haven't even gotten to the logic board issues and with no power it's really unrewarding. I retraced some bad circuits. I resoldered some bad joints. I would love to just see a scrambled screen and a chime of some type come out of the speaker at the very least. So I know better than to throw it in the dumpster. I will post the sad little mac on the want ads. Maybe someone with a bunch of spare parts lying around can frankenstein it. Thanks for the laughs. I enjoyed it while it lasted.
  7. cfriberg

    smoking yoke

    Wow, you guys are brutal. OK, so I found a big problem and I hope I fixed it. The board is cracked right at the "high voltage connector?" This is where the neck board was caught smoking Here's just some more pics to make this thread more "useful". So what do you think? Should I try powering it up again and see if that crack caused a short and was the source of the smoke or would it be the little black transistor on the neck board like you said earlier?
  8. cfriberg

    smoking yoke

    Ha ha uniserver, I think your analog board needs to be recapped. Anyways, I tried to be respectable and figure out where the output transistor is on my own, but I give up. I found a funny picture on the way though: https://flic.kr/p/4F81tG Also, what's the best way to detach the CRT from the analog board so I can do some more investigating on the board without being tied down to a possibly dead glass tube?
  9. cfriberg

    smoking yoke

    The deflection yoke? There are 7 pins at the butt end of the CRT past the yoke, attached to these pins is a plastic connector on a PCB. The smoke was coming from somewhere on that little PCB. I don't want to turn it on again and wait for more smoke to see exactly where it's coming from. I was hoping someone had this issue before. I did read something about people having problems with dry solder joints somewhere on the yoke, maybe this is the problem? I'm not sure which joints commonly fail. Anyways, thanks to anyone who can give me a clue.
  10. cfriberg

    PRAM Batteries

    Any luck getting that corroded board to work? I have the same problem and am hoping to revive my classic. So far all i have done is a cosmetic cleaning. I see corroded diodes on the back of the board and corroded traces on top. Also, will it run with the battery case completely removed if all else is functional or will i need to find a new one?
  11. cfriberg

    smoking yoke

    Hi everyone I'm digging up my old mac classic with the hopes of reviving it. I know its gonna have lots of problems but i hope it ends up a happy mac story. The first most important i think is on power up i get a screaming sound that i think originates from the analog board, hopefully just the speaker but it was followed by smoke coming from the yoke connector. I dont see any signs of burning though so i dont know what is extactly is smoking. I need to exorcise this demon before i can start troubleshooting other issues. Any thoughts? Did a search for smoke and yoke connector and i dont see anyone else with this problem. Thanks and happy classic mac-ing
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