[Angelo Campanella]

I have an old stereo with a 5-disk player that I want to use for general
background music throughout the day.... but it skips badly on many of my old
favorite discs accumulated over the years. They all play well on other
single-CD players including in my car.

But this old 5-disk unit skips badly for most of those CD's. The
changing mechanism works well, but tracking is not nearly up to snuff.

One or two discs will work reliably. "Carmena Burana" (TELARC, Stero CD
80056) tracks well, but faint levels are too faint, I think. That leads me
to believe that the tracking mechanics, gears, etc are OK. But maybe the
amplifiers, Dolby or filters are not up to spec.

Other CDs including "Brandenburg Concertos", (TELARC 20 bit 2CD-80412)
are hopeless when cold, but about 60% trackable after long warm-up. Still
other CDs won't even lock in but jump quickly band-to-band until they run
out and the player trundles to the next disc.

On opening up and scrutinizing the optic head assembly (lens now wiped
clean of any dust) I see three miniature pots on the lens carriage... Do
those pots provide any useful adjustment?

Comments?

Angelo Campanella

[William Sommerwerck]

Poor tracking is often due to a deteriorating laser. The pots might help,
but don't adjust them without knowing what you're doing.

[N_Cook]

Angelo Campanella wrote in message
...
I have an old stereo with a 5-disk player that I want to use for
general
background music throughout the day.... but it skips badly on many of my
old
favorite discs accumulated over the years. They all play well on other
single-CD players including in my car.

But this old 5-disk unit skips badly for most of those CD's. The
changing mechanism works well, but tracking is not nearly up to snuff.

One or two discs will work reliably. "Carmena Burana" (TELARC, Stero
CD
80056) tracks well, but faint levels are too faint, I think. That leads me
to believe that the tracking mechanics, gears, etc are OK. But maybe the
amplifiers, Dolby or filters are not up to spec.

Other CDs including "Brandenburg Concertos", (TELARC 20 bit
2CD-80412)
are hopeless when cold, but about 60% trackable after long warm-up. Still
other CDs won't even lock in but jump quickly band-to-band until they run
out and the player trundles to the next disc.

On opening up and scrutinizing the optic head assembly (lens now wiped
clean of any dust) I see three miniature pots on the lens carriage... Do
those pots provide any useful adjustment?

Comments?

Angelo Campanella


Assuming the skips do not occur at the same mechanical point of all CDs and
so gear/rack problem

If you do adjust any pots , measure ohms of each to 3 figures before
fiddling, and measure each way just in case a difference. And only a minimal
amount of change each time. Find a CD and specific track that at the moment
gives a consistent amount of seconds of skip, to monitor against

[Meat Plow[_5_]]

On Sat, 06 Nov 2010 12:09:44 -0400, Angelo Campanella wrote:

I have an old stereo with a 5-disk player that I want to use for general
background music throughout the day.... but it skips badly on many of my
old favorite discs accumulated over the years. They all play well on
other single-CD players including in my car.

But this old 5-disk unit skips badly for most of those CD's. The
changing mechanism works well, but tracking is not nearly up to snuff.

One or two discs will work reliably. "Carmena Burana" (TELARC, Stero
CD
80056) tracks well, but faint levels are too faint, I think. That leads
me to believe that the tracking mechanics, gears, etc are OK. But maybe
the amplifiers, Dolby or filters are not up to spec.

Other CDs including "Brandenburg Concertos", (TELARC 20 bit
2CD-80412)
are hopeless when cold, but about 60% trackable after long warm-up.
Still other CDs won't even lock in but jump quickly band-to-band until
they run out and the player trundles to the next disc.

On opening up and scrutinizing the optic head assembly (lens now
wiped
clean of any dust) I see three miniature pots on the lens carriage...
Do those pots provide any useful adjustment?

Comments?

Angelo Campanella

One pot adjusts the laser intensity which could compensate for aging but
it probably would just hasten the inevitable complete failure of the
laser block.



--
Live Fast, Die Young and Leave a Pretty Corpse

[Clyde]

On 06/11/2010 16:56, Meat Plow wrote:
On Sat, 06 Nov 2010 12:09:44 -0400, Angelo Campanella wrote:

I have an old stereo with a 5-disk player that I want to use for general
background music throughout the day.... but it skips badly on many of my
old favorite discs accumulated over the years. They all play well on
other single-CD players including in my car.

But this old 5-disk unit skips badly for most of those CD's. The
changing mechanism works well, but tracking is not nearly up to snuff.

One or two discs will work reliably. "Carmena Burana" (TELARC, Stero
CD
80056) tracks well, but faint levels are too faint, I think. That leads
me to believe that the tracking mechanics, gears, etc are OK. But maybe
the amplifiers, Dolby or filters are not up to spec.

Other CDs including "Brandenburg Concertos", (TELARC 20 bit
2CD-80412)
are hopeless when cold, but about 60% trackable after long warm-up.
Still other CDs won't even lock in but jump quickly band-to-band until
they run out and the player trundles to the next disc.

On opening up and scrutinizing the optic head assembly (lens now
wiped
clean of any dust) I see three miniature pots on the lens carriage...
Do those pots provide any useful adjustment?

Comments?

Angelo Campanella

One pot adjusts the laser intensity which could compensate for aging but
it probably would just hasten the inevitable complete failure of the
laser block.



The laser assembly in older Sony units is usually a KSS150A or KSS210A
(number visible on assembly panel). These tend to fail, I used to
replace these often in even then new CD units. You may even find one
knocking around as a lot of the budget brands also used this pick-up.
Failing that this particular optical unit is cheap to buy, have a look
on eBay.

To me it does sound like laser failure. As far as the pots are
concerned, I've never had much luck altering these, you really need a
laser power meter, and you have to be very careful as the laser diode is
easily damaged.

[Mark Zacharias[_3_]]

"Angelo Campanella" wrote in message
...
I have an old stereo with a 5-disk player that I want to use for
general background music throughout the day.... but it skips badly on many
of my old favorite discs accumulated over the years. They all play well on
other single-CD players including in my car.

But this old 5-disk unit skips badly for most of those CD's. The
changing mechanism works well, but tracking is not nearly up to snuff.

One or two discs will work reliably. "Carmena Burana" (TELARC, Stero CD
80056) tracks well, but faint levels are too faint, I think. That leads me
to believe that the tracking mechanics, gears, etc are OK. But maybe the
amplifiers, Dolby or filters are not up to spec.

Other CDs including "Brandenburg Concertos", (TELARC 20 bit 2CD-80412)
are hopeless when cold, but about 60% trackable after long warm-up. Still
other CDs won't even lock in but jump quickly band-to-band until they run
out and the player trundles to the next disc.

On opening up and scrutinizing the optic head assembly (lens now wiped
clean of any dust) I see three miniature pots on the lens carriage... Do
those pots provide any useful adjustment?

Comments?

Angelo Campanella



STOP. Don't go adjusting anything except as a last resort. Clean the laser
lens, lubricate the spindle motor shaft where it enters the motor body. Do
the same for the sled motor and re-grease the gears and lubricate the slide
rail and over on the other side of the pickup where it slides along the
pickup base.
You have described a KSS 240 or 240A pickup. The flat cable they used to
connect the pickup to the board may have developed stress cracks from
flexing. This was a common problem and may require the cable be replaced.
The pickup itself is probably OK, but you never know; the 240's would
occasionally be intermittent.

Mark Z.

[Brenda Ann[_2_]]

"Clyde" wrote in message
...
The laser assembly in older Sony units is usually a KSS150A or KSS210A
(number visible on assembly panel). These tend to fail, I used to replace
these often in even then new CD units. You may even find one knocking
around as a lot of the budget brands also used this pick-up. Failing that
this particular optical unit is cheap to buy, have a look on eBay.

To me it does sound like laser failure. As far as the pots are concerned,
I've never had much luck altering these, you really need a laser power
meter, and you have to be very careful as the laser diode is easily
damaged.

When CD players were still a new thing, I bought a middle of the line Sony
unit, along with a complete AV system. Things led to other things, and
everything went into storage before I ever got to use it. Two years later, I
got it out of storage, hooked everything up. It all worked, but the CD
player... no love there. I could see a very dim and diffuse red light coming
from the laser head, but no 'beam'. I opened it up to see what was up, and
found spider eggs of all things inside. I removed the spider eggs, but never
could get the laser back in alignment.... I ended up ordering a new head
assembly.

Lots of fun.... NOT.

[Arfa Daily]

"Clyde" wrote in message
...
On 06/11/2010 16:56, Meat Plow wrote:
On Sat, 06 Nov 2010 12:09:44 -0400, Angelo Campanella wrote:

I have an old stereo with a 5-disk player that I want to use for general
background music throughout the day.... but it skips badly on many of my
old favorite discs accumulated over the years. They all play well on
other single-CD players including in my car.

But this old 5-disk unit skips badly for most of those CD's. The
changing mechanism works well, but tracking is not nearly up to snuff.

One or two discs will work reliably. "Carmena Burana" (TELARC,
Stero
CD
80056) tracks well, but faint levels are too faint, I think. That leads
me to believe that the tracking mechanics, gears, etc are OK. But maybe
the amplifiers, Dolby or filters are not up to spec.

Other CDs including "Brandenburg Concertos", (TELARC 20 bit
2CD-80412)
are hopeless when cold, but about 60% trackable after long warm-up.
Still other CDs won't even lock in but jump quickly band-to-band until
they run out and the player trundles to the next disc.

On opening up and scrutinizing the optic head assembly (lens now
wiped
clean of any dust) I see three miniature pots on the lens carriage...
Do those pots provide any useful adjustment?

Comments?

Angelo Campanella

One pot adjusts the laser intensity which could compensate for aging but
it probably would just hasten the inevitable complete failure of the
laser block.



The laser assembly in older Sony units is usually a KSS150A or KSS210A
(number visible on assembly panel). These tend to fail, I used to replace
these often in even then new CD units. You may even find one knocking
around as a lot of the budget brands also used this pick-up. Failing that
this particular optical unit is cheap to buy, have a look on eBay.

To me it does sound like laser failure. As far as the pots are concerned,
I've never had much luck altering these, you really need a laser power
meter, and you have to be very careful as the laser diode is easily
damaged.

If the laser has 3 pots on it, then it will be a KSS240A. The pots will be
sealed with white paint, and must not be changed from their sealed factory
settings. '240A's regularly wear out in the way described. It is an easy
laser to replace, but one word of warning. You will not get away with
replacing it with a second source clone or an NKS240A. It must be a genuine
Sony *original* part, preferably sourced from Sony themselves. Although
clone '240A's seem to work fine in other manufacturers' players, Sony
players are *exceptionally* critical of having a genuine one fitted, and if
you put a cheapo in, it may perform little better than the one you are
taking out. I have even known them to refuse to work at all in a Sony. Other
Sony lasers such as KSS213's in all flavours, seem to be fine with clones.
Just the 240 which is a problem.

Arfa

[Angelo Campanella]

"Clyde" wrote in message
...
The laser assembly in older Sony units is usually a KSS150A or KSS210A
(number visible on assembly panel). These tend to fail, I used to replace
these often in even then new CD units. You may even find one knocking
around as a lot of the budget brands also used this pick-up. Failing that
this particular optical unit is cheap to buy, have a look on eBay.

When it runs, I see no light at all. Shouldit be red or bue? There are
infrared style lasers that run around 1.1 microns wavelength (visible is 1/2
micron).

So what do I look for to buy a replacement? and if I get one, how do I
install it?

To me it does sound like laser failure. As far as the pots are concerned,
I've never had much luck altering these, you really need a laser power
meter, and you have to be very careful as the laser diode is easily
damaged.

If it is vsible light, it shoud be quite evident.

Another thing, this sensor appears to position its lens right up against
the CD disk... If it's spaced away, it an't be more than a millimeter or so.

I mic'd the disk thicknesses. They are all 41 to 42 mils thick, about
1.05mm.

Ange