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Can someone help me do a minor fix to my stereo?

I have a four-year old Aiwa/Sony shelf stereo. I am having a problem with it. With some CDs, particularly some that seem a bit lighter in weight, I am getting a horrible whining noise and sometimes the thing even starts skipping.

I started to get rid of the thing, but after shopping around, I discovered that it's superior to any other shelf system I checked out, plus I determined that I simply don't have the space, resources, etc., right now to assemble a component setup in my bedroom, which is where this stereo is. So I decided to keep the thing and try to get it fixed.

I know, from a Sony Technical Bulletin, that this issue is caused by an oscillation problem with the specific Sony optical pickup (KSS-240A) that's installed on the thing, that causes a mechanical resonance issue with the discs as they play. I know, from a Sony Technical Bulletin, that the fix for this is to add a brass weight (part No. 4-962-979-01) to the pickup, and a felt washer (part No. 4-986-769-01) to the surface of the clamper that touches the disc. The screw (part No. 7-685-134-19) that adds the weight to the pickup replaces the screw that holds the PC board with the pots to the laser. I have these parts in hand from Sony, ready to install. I have spent the morning trying to find someone to install them, since I've never done this kind of thing before. I've discovered that no one works on stereos anymore. I'm not surprised of this, because I'm sure they're considered kind of disposable. But I don't want to dispose of this one when all that needs to be done is a piece of brass screwed in somewhere and a piece of felt stuck somewhere.

Let me take that back, there is one person in my town who will do such work, and he's very good and quite cheap. The only problem is I might get the stereo back around Inauguration Day ... of 2013.

So, is there anyone out there who could clue me in on just how big a deal what I have described is to execute, whether it's something a do-it-yourselfer should even attempt or should I still beat the bushes trying to find somebody to do it. And if it is something simple that I could do, could you give me "See Spot Run" simple, hand-holding directions, starting from the moment I take the first screw out of the thing, as to how I do it, what exactly I need to look for, what do I need to be careful of, etc., because I really don't want to trash the thing trying to fix it. Because I really have no clue whatsoever where or what these specific things (clamper, PC board with pots, pickup, laser, etc.) are or look like.

Thanks in advance for any help.

Reply to
Greg Bailey
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Did it come with any instructions? If you have a screwdriver you ought to be able to fix this yourself, it should only take a few minutes. If you're really that much of a newbie, I suggest finding someone local to help, don't you have any engineer or handyman friends or neighbors? It would be very hard for someone to give you such detailed instructions over the internet without being familiar with that particular unit.

Reply to
James Sweet

No, all I got was a piece of felt, a brass weight and a screw. I've been trying to find a diagram of that particular pickup online, to use as reference, without any success so far.

Reply to
Greg Bailey

Have a look here:

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The optical pickup is the lens you see which is on a sled which moves horizontally as the CD spins. As in the picture in the above link, the pickup head is often attached to a small circuit board with some focus/tracking components. You can actually see a screw in the picture, although yours might be somewhat different it shouldn't be rocket science to open it up, remove a screw holding the laser assembly to the attached PCB, and install the brass one. Be careful not to move any of the pots (they'll probably have a drop of adhesive keeping them from moving) as that will mess up your focus/tracking/alignment. As far as the hunk of felt, I assume it's got sticky backing on it on one side? When you open up the player, there is, to use Sony's term, a "clamper" which grabs the CD, allowing the spindle motor to spin it. You need whatever is attached to the spindle motor (called "disks drive" in the picture) to have friction on the disc, so I'd think the felt washer would go on the other side (which would be the top), but it should be obvious where the washer will fit once you get things opened up.

Don't worry about this one: it's not at all a technical repair and if you are careful, it'd be pretty hard to break anything.

Dave

Reply to
Dave

THANK YOU!!! This is exactly what I needed. And it looks like I'm going to be the one to do it, no local techs would fool with it.

Reply to
Greg Bailey

piece of felt, a brass weight and a screw. I've been

Here's a picture of the KSS-240A pickup:

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You can see the screw to the left of the label.

The other thing to be careful of is ESD (Electrostatic Discharge). If you don't have an antistatic wrist strap, at least take some common sense precautions: minimize plastic and fabrics (carpet, wool or acrylic sweater) in the vicinity of your repair, pick a more humid day or area to do the repair, and touch the metal chassis of the stereo system (if it has one) before approaching the pickup or other electronic devices with your hands.

TM

Reply to
tonym924

Gotcha ... I've done work inside my computer before so I know about avoiding ESD.

Reply to
Greg Bailey

Hilarious. This is what I used to use on my record player when the tone-arm skipped.

If you are inclined to email me for some reason, remove NOPSAM :-)

Reply to
mm

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