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CDRom2 need a few values

Started by Slypty, 12/25/2018, 12:37 PM

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Slypty

I had the pleasure of getting a faulty CDRom2 to fix up, CD would hardly spin.  The spindle rod was badly corroded, and after replacing it I still had very little movement.
Completed a full recap and pulled a few solder tabs, this board was one of the more brittle one's.

Picture 1
  On C215 and C216 are two small 4.7uF Caps.  I think my replacement caps legs were too big, because they ripped the tabs out completely.  I could trace one terminal (both on the right side of the pic, and re-solder to another attached tab), but the other which is surrounded by a square I couldn't find any traces leading in to the terminal where the tab was lifted.  I scraped around that area but didn't reveal any copper leads.  My thought it was a simple ground, so I ran a ground wire to these legs.  I really couldn't see any traces leading in to the terminal, even under 10x magnification.   My concern is since it's a double layered PCB the top of the board may have a lead in to C215 and C216, but I also don't seem to see traces leading in to those caps from the top of the board.   Also if you see the lifted trace near the top of the pic, it was fixed by attaching to trace lead (see on the right side of the broken tab.)

  Here's a few pics of what I've done.. a little hard to see, but the two terminals with wires attached are wired to ground, and just thinking this could be an error or if anyone has a better concept of where these tabs lead to. 

Picture 2

This pic just shows a missing resistor, it seems to be a bit to clean maybe for a missing resistor, (under C161) but wanted to know the value in case this one is actually missing.  Hopefully someone's got one open they can have a quick look at these areas, thanks for any help

NightWolve

Did you try the search feature already to see if there are screenshots of the PCB ?? Gotta be something lying around somewhere...

Slypty

I've tried but they're too hard to see for specific areas.. also, it would be tough if it's a specific value to know what to replace it with.
Anyways I'm picking up another CD unit soon to repair.

  A general question would be, do some motherboards have 'markings' like R201 or C305 etc where there's actually no fitted resistor or small cap?  I know for bigger caps (radial etc) it's common to have nothing there, but I'm not sure about the smaller components.