CD player problem

Try cleaning the laser. If this does not fix it, there is a chance that there is a mechanical problem, or the laser is getting weak.

--

Jerry G. ======

-- "The difference between intelligence and stupidity is that intelligence has its limits."

If you wan to pursue it further, see the CD Repair Guide at the sites below.

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If you are able to open and look into the actual drive as it operates, see if it makes incorrect contact at the clamp (spindle mechanism). If it makes contact it may eject it to prevent damage to the disc. A motion sensor may also be dirty or bad. The clamp itself may not work well and the disc may not read. Use of a cleaning CD may not be useful as the cycle may fail prior to encountering the cleaning device. My experience is that Sony players tend to display "no disc" more often than ejection in the event of a failed read, so an obstruction or sensor problem is likely, followed by the lens, which may need more invasive, less user-accomplished cleaning techniques or possibly alignment or replacement of the laser. You do not state the model or listed mfg. date. I have standalone CDPs dating back to 1987 by Sony and I haven't encountered a bad laser yet.

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has

I have an "older" Sony CDP c505 5 disc player that has sound problems as you go past track 3 or 4 (or to the outer edge of the CD itself) it is kind of like cutting in and out and distortion ? Any adjustements I can do to make this go away?

First check that the sled movement is absolutely free - that there is no no grease on the slides that has gone 'sticky'. Problem could also be the sled motor, the spindle motor, possibly the laser itself (make sure that the lens is absolutely clean and shiny), or the surface mount electrolytics on the servo board that are known trouble causers on the older Sonys. It is unlikely that your problem can be cured by adjustment. Do not attempt random adjustment, as this is only likely to compound the problem.

Arfa

Could also be a gear with a missing tooth - I had a Sony Discman which had that problem, about 20 minutes into a disc it would get stuck at one spot and just keep repeating. The missing gear tooth was on the drive which moved the optical pickup from the centre to the edge during play.

Quite so, I'd forgotton that one, but you will of course pick up that problem when checking the sled for freedom of movement. Another fairly common one that can cause the same problem, is a split in the nylon pinion on the shaft of the sled motor. If you push the sled manually down the slides, you can feel it go bump-bump-bump as the gears rotate. Nothing can be done about that one, except to replace the pinion from a scrap deck.

Arfa

grease on the slides that has gone 'sticky'.

Thanks, but I probably did not explain the problem very well, the laser assembly moves back and forth fine. The problem with the outer tracks is the sound quality deteriorates as you go farther out on the edge of the discs. It is not skipping, it seems the sound goes high and low and is slightly distorted as well?

The official stuff is called "floil". It's a white synthetic lubricant a little thicker than light oil, but thinner than you would usually consider as 'grease'. I have an aerosol can of a light synthetic machine oil called "CMO" (Clear Machine Oil) made by Electrolube. It's a little thicker than sewing machine oil, and has very good 'cling' characteristics on chrome plated slide rods, and seems to lubricate nylon against metal quite acceptably. It is also absorbed readily into phosphor bronze 'oilite' type bearings that are found on sled and spindle motors, and sometimes on the laser slide rod bearing surfaces. It is a good all-round product for all the lubrication jobs on a CD / DVDdeck, and I have used it for just this, on a daily basis, for some years.

Arfa

OK. Well basically, it is not possible for the system used to play a CD, to produce distorted sound as a result of track position, unless the system is dropping so many bits, that it has got beyond the capabilities of the error correction circuitry. This can occur as a result of tracks being closer to the end of a disc, for one of two reasons. The first is a defective spindle motor. As the laser tracks towards the edge of the disc, the disc's rotational speed slows to maintain a constant data rate from the pickup. If the motor gets poor, this can result in its shaft speed becoming erratic. The slower the motor is running, the more pronounced the problem is, until data starts to become so mis-timed that bits start getting dropped. This can result in a harsh 'crackly' sort of distortion that can get as bad as total music drop-out, as the error correction throws up its arms in dispair, and instead mutes.

I have also known a similar thing to occur with a weak laser. Now in theory, there is no real reason that this should happen, as the reduced disc speed, should result in the laser seeing data at exactly the same rate. I suspect that it is in fact a combination of both a slightly worn, and thus slightly unstable motor, with a weak laser. If the laser is replaced, the marginal motor becomes 'masked' and the player works fine again. Motor is now the first place I would be looking.

Arfa

On Apr 1, 12:55 pm, "Arfa Daily" wrote: Another fairly

Sorry to hijack this thread. Just remembered something. ARFA: I have an ONKYO cd player gathering dust with this cracked sled pinion problem; any ideas on sourcing a replacement or shall I just toss it? (it's not a 'high end' deck anyway).

-B.

Hi B

I have found that in general, most of the pinions are about the same size, and you can usually get away with + / - one tooth without noticing a problem. The shaft size is close enough on all of the motors that are currently used. Most come from the Mitsumi stable anyway. I keep a junk box with a variety of old decks for exactly the reason of culling odd little parts like this, that would otherwise write off a perfectly good item. If you don't have such a thing yourself, it would be worth paying a visit to any local repair shop that you might still have near you. They are sure to have piles of scrap CD and DVD players out back, that they would be happy for you to relieve them of. Another possibility might be an old computer CD drive ? Local waste tip also ? I see lots of the cheapo little supermarket hifis dumped at my local recycling centre. Often, these have a CD player in the top, and just by opening the lid, you can see if the deck is in any way similar enough to yours to have a part that you can use. I don't see much Onkyo stuff, so I don't recall much about the decks that they use, but many manufacturers just use 'off the shelf' Sony or Sanyo decks, so you might even find the exact same one in the last place you might expect.

Arfa