Sony pickup whacks furiously

Dec 05, 2005 6 Replies

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Can any one help me with my CD player? It's a Sony component CD player = that uses KSS-240 pickup. My problem is, as soon as the player is = powered on, the lens head will be immediately starting whacking up and = down, something like machine gun fires. The objective lens overshoots = and hits, making a sound somewhere like 10hz beating/whacking sounds. It = won't stop until powered off. Does anyone know how I can fix this?



Thanks a lot,



SY


Hello,

You did not mention what CD player the pickup is in, but a rapid fire of the lens like that is not likely to be the pickup. It is more likely to be a driver IC problem or a clock failure.

Regards, Tim Schwartz Bristol Electronics

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Thanks a lot,

SY

If the player has what's called ( by Sony ) a ' B ' board mounted = immediately under the deck, with the spindle and sled motors soldered = straight into it, look for 3 or 4 surface mount electrolytics along one = edge - there's various versions of this board.

I think that they are 47uF as I recall. They commonly go open circuit, = but also, one of them is prone to actually leak, and the electrolyte = usually attacks a nearby through plated hole, which must then be ' wired = around '. It is ESSENTIAL that the caps are replaced with similar = surface mount types. Ordinary wire ended types WILL NOT work. All of = these caps are on pins of the servo processor IC, and the symptoms you = describe are typical of their failure.

Arfa

Sy,

Besides driver IC's and clocks, you could have a very noisy power supply. You'll need to look at the supplies with a scope.

Regards again, Tim

=_NextPart_000_000B_01C5FB3E.B962EF20 Content-Type: text/plain; charset="ks_c_5601-1987" Content-Transfer-Encoding: quoted-printable

Dear Arfa,

I was able to locate those 3 electrolytics and confirm that leakage from = the middle one!!! It caused the neighboring parts and plated holes = spoiled and eroded. Now my quest is how and where to get the surface = mount electrolytics...

Thanks for your wonderful help and amazing knowledge!

Thanks a lot,

SY

If the player has what's called ( by Sony ) a ' B ' board mounted = immediately under the deck, with the spindle and sled motors soldered = straight into it, look for 3 or 4 surface mount electrolytics along one = edge - there's various versions of this board.

I think that they are 47uF as I recall. They commonly go open = circuit, but also, one of them is prone to actually leak, and the = electrolyte usually attacks a nearby through plated hole, which must = then be ' wired around '. It is ESSENTIAL that the caps are replaced = with similar surface mount types. Ordinary wire ended types WILL NOT = work. All of these caps are on pins of the servo processor IC, and the = symptoms you describe are typical of their failure.

Arfa

=_NextPart_000_01D8_01C5FB1D.D2B7C750 Content-Type: text/plain; charset="ks_c_5601-1987" Content-Transfer-Encoding: quoted-printable

I was able to locate those 3 electrolytics and confirm that leakage = from the middle one!!! It caused the neighboring parts and plated holes = spoiled and eroded. Now my quest is how and where to get the surface = mount electrolytics...

Thanks for your wonderful help and amazing knowledge!

SY Hi there

You should be able to get exact replacements, or similar types, from =

virtually any regular component supplier. You can get away with = slightly=20 higher voltage working ones, which are more readily available. If = memory=20 serves, the originals are rated at 4v working, and replacements at =

6.3v=20 working are more readily available. However, they are slightly = larger, so=20 you've got to be a bit a bit more careful fitting them.

I don't know whereabouts in the world you are, but here in the UK, = they are=20 available from

formatting link
under part number=20 5397736 but they are special order, which is usually 7 -10 days = delay,=20 and I don't know if they have international shipping arrangements. = The=20 manufacturer seems to be Jaeger, so maybe you could do a search on = that.

When you come to fit replacements, it is essential that all of the = leaked=20 electrolyte is removed from the board, and the affected area = chemically=20 neutralised. You can do this using electronics grade ( 99.7% ) = isopropyl=20 alcohol, and an old toothbrush.

Also, it is essential, if it is to ever work again, that the damaged = through=20 plated holes are properly dealt with. Use a strong magnifier, or = jeweller's=20 eyepiece to examine the areas where the tracks join the edges of the =

affected holes. You will often find that if you give this area a = little=20 scrape with a blunt curve-blade scalpel edge to remove the = blackening, that=20 the actual track is eaten away. As I recall, it's difficult to see = where at=20 least one of the tracks finally goes to, as once it has gone to the=20 underside of the board, it goes for a short distance, then comes up = again=20 through another through plated hole to the top of the board, but = under the=20 servo processor IC, where you then can't see what pin it finishes up = at.

At a pinch, you can carefully drill out any affected holes where you = can get=20 at both sides, using a model-makers drill, and feed a thin wire = through the=20 hole, soldering to the nearest piece of undamaged track on the run = to the=20 hole, on both sides.

If you can tell me the model number of the CD player, I might have = the=20 manual, or a similar one that we can use to determine exactly to = where each=20 cap is ultimately connected.

I have done many of these over the years, though not so many = recently, as=20 they are getting old now. They are definitely always repairable in = the end,=20 but require much patience to repair the damage caused, and may cause = you=20 more than a little frustration along the way ...

Arfa

=_NextPart_000_0013_01C5FC02.D9F9D450 Content-Type: text/plain; charset="ks_c_5601-1987" Content-Transfer-Encoding: quoted-printable

Dear Arfa,

You make me clearly envision what to do over the coming weekend. No = problem with the old toothbrush... I live in Seoul, Korea. I may go out = to electoronic parts shops to buy the part. Normally the vendors out = there don't treat a customer like me well who choose to purchase an item = by 1-2 in quantity. So, one of my realistic alternatives would be = wandering around Sony service center junkyard, very luckily I have one = nearby, to look for a scrap.

The CD player came out from Sony mini component system, FH-E838CD. The = player has its own model number of CDP-H3600. Personally this is an = important project. In order to re-establish the order within the family, = recently I declared to my family members, my wife more particularly, = that it will be fixed by me (to prove that I do have and maintain a = sound and still working brain system). As I became weak-sighted, looking = tiny things becomes an obstacle. Yes, I think I need jeweller's = eyepiece. I hope a sunny and clear weekend for the operation. I also = like your encouragement: Its always repairable.

Thanks a lot.

SY

I was able to locate those 3 electrolytics and confirm that leakage = from the middle one!!! It caused the neighboring parts and plated holes = spoiled and eroded. Now my quest is how and where to get the surface = mount electrolytics...

Thanks for your wonderful help and amazing knowledge!

SY Hi there

You should be able to get exact replacements, or similar types, = from=20 virtually any regular component supplier. You can get away with = slightly=20 higher voltage working ones, which are more readily available. If = memory=20 serves, the originals are rated at 4v working, and replacements at =

6.3v=20 working are more readily available. However, they are slightly = larger, so=20 you've got to be a bit a bit more careful fitting them.

I don't know whereabouts in the world you are, but here in the UK, = they are=20 available from

formatting link
under part = number=20 5397736 but they are special order, which is usually 7 -10 days = delay,=20 and I don't know if they have international shipping arrangements. = The=20 manufacturer seems to be Jaeger, so maybe you could do a search on = that.

When you come to fit replacements, it is essential that all of the = leaked=20 electrolyte is removed from the board, and the affected area = chemically=20 neutralised. You can do this using electronics grade ( 99.7% ) = isopropyl=20 alcohol, and an old toothbrush.

Also, it is essential, if it is to ever work again, that the = damaged through=20 plated holes are properly dealt with. Use a strong magnifier, or = jeweller's=20 eyepiece to examine the areas where the tracks join the edges of = the=20 affected holes. You will often find that if you give this area a = little=20 scrape with a blunt curve-blade scalpel edge to remove the = blackening, that=20 the actual track is eaten away. As I recall, it's difficult to see = where at=20 least one of the tracks finally goes to, as once it has gone to = the=20 underside of the board, it goes for a short distance, then comes = up again=20 through another through plated hole to the top of the board, but = under the=20 servo processor IC, where you then can't see what pin it finishes = up at.

At a pinch, you can carefully drill out any affected holes where = you can get=20 at both sides, using a model-makers drill, and feed a thin wire = through the=20 hole, soldering to the nearest piece of undamaged track on the run = to the=20 hole, on both sides.

If you can tell me the model number of the CD player, I might have = the=20 manual, or a similar one that we can use to determine exactly to = where each=20 cap is ultimately connected.

I have done many of these over the years, though not so many = recently, as=20 they are getting old now. They are definitely always repairable in = the end,=20 but require much patience to repair the damage caused, and may = cause you=20 more than a little frustration along the way ...

Arfa

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