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cdrom2 lasers keep dying

Started by Snow Crash, 07/16/2012, 10:57 AM

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Snow Crash

So, i'm on my third laser in my cdrom 2 (white Japan model) in as many weeks. The first 2 where old units salvaged from a walkman and another cdrom2 unit, so I figured it was, perhaps, just thier time to go. However, after getting a brand new laser from BlueBMW (delivered very quickly might I add), this to has died. This leads me to think that the cdrom2 itself might have a fault that is killing the lasers or the pots are so out of whack that the laser's over-volting or something similar.

The scenario so far has been; once the new laser is installed it works OK, but, audio tracks cut out after a few seconds. I've adjusted the pot slightly and the problem will be temporarily resolved, then the laser dies.

I only have one laser from BlueBMW left now, so if anyone's got any suggestions I'd be very appreciative.

BlueBMW

Hmmm, ill bet steve can chime in on this one.  Let me know if you need more lasers.  Its possible you just got a bad one.  Though theyre new, they are old so defects are possible.
[Sun 23:29] <Tatsujin> we have hard off, book off, house off, sports off, baby off, clothes off, jerk off, piss off etc

Snow Crash

IMG

Thanks BlueBMW, hopefully I shall not need any more but, I guess I probably will :( . I Think it is unlikely that the one you sent me would die in exactly the same way as the others if there wasn't a reason for it.

Here's what the pots are set at at the moment. I spent ages adjusting them so the tracks wouldn't skip. Does anything look too extreme? If anyone has a KS-225A in there cd rom 2 and could take a picture of their settings that'd be excellent.

thesteve

your trims look right.
try removing and reinstalling the same laser.
often dead solder joints can cause faults that vanish when moved/disassembled, only to reappear later.

Snow Crash

Ok, tried your suggestion Steve, but no luck, also tried re-installing a laser i previously thought was dead, just in case, also dead. I'll try the other new laser from BlueBMW tomorrow,but i'm wary of the same thing happening. :(

BlueBMW

Quote from: snow Crash on 07/17/2012, 08:02 PMOk, tried your suggestion Steve, but no luck, also tried re-installing a laser i previously thought was dead, just in case, also dead. I'll try the other new laser from BlueBMW tomorrow,but i'm wary of the same thing happening. :(
Well I've got tons more, so if it blows another then we will know for sure that its something in the CDROM2 doing it.  If not, then we know we got a bad new laser and I'll send you another one or refund you for that one.
[Sun 23:29] <Tatsujin> we have hard off, book off, house off, sports off, baby off, clothes off, jerk off, piss off etc

thesteve

with the lid up does the laser turn off (had a bad chip that wouldnt)

Snow Crash

Quote from: thesteve on 07/17/2012, 11:55 PMwith the lid up does the laser turn off (had a bad chip that wouldnt)
Nope, this has never happened.

OOOOOOOOOOkay, put the new laser in and nothing happens at all. It's dead. Only get the led display and that's it, laser doesn't light, or move. I've been checking it and removing it and re-installing it over and over again. So I'm guessing I should give up on it now.

BlueBMW

Ill assume your gears are working good?
[Sun 23:29] <Tatsujin> we have hard off, book off, house off, sports off, baby off, clothes off, jerk off, piss off etc

thesteve

if you push the laser sled to the edge does it return to center when you hit play?

Snow Crash

Quote from: BlueBMW on 07/18/2012, 04:30 PMIll assume your gears are working good?
Yup, new replacements from Chop5
Quote from: thesteve on 07/18/2012, 05:05 PMif you push the laser sled to the edge does it return to center when you hit play?
Nope. Nothing.

Going to swap the main-board from a smashed up cdrom2 unit into this one to see what happens. I think that board is ok.

Snow Crash

Okay, the other board exhibits the same behaviour. So, maybe it is the laser. Am I really that unlucky?  :-k

thesteve

its the gears if it didnt center