So i have this on my bench as it was given to me for free. Initially it was playing CD's poorly, and wouldnt recognise CD-R's at all. A little cleaning and focus adjustment helped, but the eye pattern was quite bad and the amplitude of the RF seemed low. I guess the laser is at the end of its life
However while I was taking measurements from the TE testpoint, it suddenly stopped. Now it wont play anything at all, and while initially the lens does its normal focus seek, the lens will regularly slam quite hard fully upward. It does this about 3 times and gives up. I can see laser output if I force the laser on using the test mode.
Is the pickup dead, or is something else wrong with the unit?
However while I was taking measurements from the TE testpoint, it suddenly stopped. Now it wont play anything at all, and while initially the lens does its normal focus seek, the lens will regularly slam quite hard fully upward. It does this about 3 times and gives up. I can see laser output if I force the laser on using the test mode.
Is the pickup dead, or is something else wrong with the unit?
A weak or dead laser wouldn't cause the lens to slam hard to the end-stops during focus search so I would suggest something else is going on. The low RF sounds like an issue on its own.
I'm not familiar with the player at all but my thoughts would be to look at the supplies to the focus drive amp (for one being intermittent if its running split supplies) or for problems with the focus drive amp itself such as dries or an intermittent output transistor.
Beyond that and things get a lot more involved in trying to narrow it down.
I'm not familiar with the player at all but my thoughts would be to look at the supplies to the focus drive amp (for one being intermittent if its running split supplies) or for problems with the focus drive amp itself such as dries or an intermittent output transistor.
Beyond that and things get a lot more involved in trying to narrow it down.
Yeah first thing I checked was the supplies to the focus amp, and those are ok. It's odd, the lens moves in its normal smooth pattern up and down, and then slams hard upward. It's almost as if some controller is telling it to do it.
TBH the player is probably going to get scrapped now as I don't think it's worth the cost of a new laser these days. It has some AD1860N-J DAC chips in so maybe I can do something with those.
TBH the player is probably going to get scrapped now as I don't think it's worth the cost of a new laser these days. It has some AD1860N-J DAC chips in so maybe I can do something with those.
That does sound a bit out of the ordinary.
The only quick thought I have would be whether the focus offset (if there is even an adjustment) is wildly off the mark and biasing the lens hard to one end. The focus search routine would probably over-ride the offset and make that part at least seem normal.
Just a thought
The only quick thought I have would be whether the focus offset (if there is even an adjustment) is wildly off the mark and biasing the lens hard to one end. The focus search routine would probably over-ride the offset and make that part at least seem normal.
Just a thought
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