Repair hints: Technics SL-P101
 

Hi!

I have the above mentioned CD player, pulled from a soggy cardboard box on
trash day, along with some computer monitors and other stuff. The monitors
have all been fine apart from some cleaning and the VCR has been working
fine after I got it dried out. That leaves me with the CD player. It looks
to be in awfully good condition for its age (not a scratch anywhere on it,
not even on the display panel) and it powers right up with no problem. At
present it has no problem reading the index of a disc, and it will play the
middle and end of a disc with no problems. The only thing it won't do is
play the beginning of a disc. I can see the spindle motor spin up and down
and I can hear the laser sled moving around from time to time as the motor
speeds up and down.

I can only see one thing that's amiss when all of this is going on. The
spindle motor seems to be having some moderate degree of difficulty coming
up to speed. It seems to do so for the most part, but it takes what I feel
is a rather long time. I am thinking that the spindle motor could be
partially shorted and in need of a cleaning. I cannot check the temperatures
of any driver components at present, because the components are on "the
wrong side" of the boards.

What I'm looking for is anyone who might have a CD player similar to this
one in working order, for reference purposes. I'm curious how quickly the
spindle motor in your player takes to come up to speed. If there is anyone
out there who has seen a similar problem (like what are my chances...but
there's no harm in asking...) with this player?

Thanks in advance for any thoughts, tips, etc!

William

Don't have any past experience with yours, but could be caused by the
Servo Output IC. Chase the cables that lead from the drive to the main
board, I'm sure the Servo IC will stick out like a sore thumb from
there. Also check in that vicinity for signs of resistors that may have
changed color, most likely not obvious with the naked eye, best to
check them for tolerance. They should be resistors in the circuit
between the IC and the motor itself.

It's not the servo IC. Maybe a lubrication issue, many old Technics models,
including I THINK yours, used direct-drive spindle motors.
The sled drive wormscrews got bad lube and bad belts as well. Of course the
optic should be cleaned.

Mark Z.

"majortom" wrote in message
oups.com...
Don't have any past experience with yours, but could be caused by the
Servo Output IC. Chase the cables that lead from the drive to the main
board, I'm sure the Servo IC will stick out like a sore thumb from
there. Also check in that vicinity for signs of resistors that may have
changed color, most likely not obvious with the naked eye, best to
check them for tolerance. They should be resistors in the circuit
between the IC and the motor itself.

"majortom" writes:

Don't have any past experience with yours, but could be caused by the
Servo Output IC. Chase the cables that lead from the drive to the main
board, I'm sure the Servo IC will stick out like a sore thumb from
there. Also check in that vicinity for signs of resistors that may have
changed color, most likely not obvious with the naked eye, best to
check them for tolerance. They should be resistors in the circuit
between the IC and the motor itself.

More likely cause is that the spindle motor is partially shorted. See:

http://repairfaq.ece.drexel.edu/sam/cdfaq.htm#cdpwspmm

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

"William R. Walsh" writes:

Hi!

I have the above mentioned CD player, pulled from a soggy cardboard box on
trash day, along with some computer monitors and other stuff. The monitors
have all been fine apart from some cleaning and the VCR has been working
fine after I got it dried out. That leaves me with the CD player. It looks
to be in awfully good condition for its age (not a scratch anywhere on it,
not even on the display panel) and it powers right up with no problem. At
present it has no problem reading the index of a disc, and it will play the
middle and end of a disc with no problems. The only thing it won't do is
play the beginning of a disc. I can see the spindle motor spin up and down
and I can hear the laser sled moving around from time to time as the motor
speeds up and down.

I can only see one thing that's amiss when all of this is going on. The
spindle motor seems to be having some moderate degree of difficulty coming
up to speed. It seems to do so for the most part, but it takes what I feel
is a rather long time. I am thinking that the spindle motor could be
partially shorted and in need of a cleaning. I cannot check the temperatures
of any driver components at present, because the components are on "the
wrong side" of the boards.

What I'm looking for is anyone who might have a CD player similar to this
one in working order, for reference purposes. I'm curious how quickly the
spindle motor in your player takes to come up to speed. If there is anyone
out there who has seen a similar problem (like what are my chances...but
there's no harm in asking...) with this player?

Thanks in advance for any thoughts, tips, etc!

It may be a partially shorted spindle motor - very common in many CD players.

See: http://repairfaq.ece.drexel.edu/sam/cdfaq.htm#cdpwspmm

The spindle motor has to spin faster on the inner tracks and can't make it.

I doubt it's the servo IC as someone else mentioned. Could be mechanical
though - deteriorated rubber parts, gummed up grease, etc.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

The SLP101 has a linear motor tracking sled, so the lubrication of the guide rails is critical.
Takes a very specific grease/oil(Panasonic molytone) to make it work properly. Probably the
cause of the problem. With the unit unpowered, picking up the front of the unit 2-3" should
make the laser slide smoothly from front to back, and vice versa picking up the back end.
Otherwise, needs lube.

--
Stephen Sank, Owner & Ribbon Mic Restorer
Talking Dog Transducer Company
http://stephensank.com
5517 Carmelita Drive N.E.
Albuquerque, New Mexico [87111]
505-332-0336
Auth. Nakamichi & McIntosh servicer
Payments preferred through Paypal.com
"Mark D. Zacharias" wrote in message ...
It's not the servo IC. Maybe a lubrication issue, many old Technics models,
including I THINK yours, used direct-drive spindle motors.
The sled drive wormscrews got bad lube and bad belts as well. Of course the
optic should be cleaned.

Mark Z.

"majortom" wrote in message
oups.com...
Don't have any past experience with yours, but could be caused by the
Servo Output IC. Chase the cables that lead from the drive to the main
board, I'm sure the Servo IC will stick out like a sore thumb from
there. Also check in that vicinity for signs of resistors that may have
changed color, most likely not obvious with the naked eye, best to
check them for tolerance. They should be resistors in the circuit
between the IC and the motor itself.

Hi!

Thanks to everyone for their excellent tips. I was leaning toward a shorted
spindle motor, but the fact that the index was always read successfully made
me wonder if that was really the problem.

Cleaning the lens gave very little improvement and I did make sure it could
slide back and forth freely. I started in to disconnecting all the cabling
leading to the CD player mechanism and just as a guess, I reseated all of
the connectors before taking the whole thing out to deal with the spindle
motor. I couldn't see anything wrong with any of them, but the player is
working perfectly now. There is no hesitation to spin up now, and the
seeking seems to happen very quickly.

I have never seen a player made quite like this one. It seems that the
spindle motor servo controller is mounted to a circuit board that the
spindle motor is also soldered directly to.

William

Hi!

Great that it works. I would caution that when repairing CD players,
often
one does almost anything and they seem to be fixed, only to have the
problem
recur, sometimes weeks or months later.

Absolutely! But at least what it confirms is that there is some bad
connection or a crack in the ribbon cable, not likely a component that
is bad.

Makes me feel good to have saved it from the garbage, at least for the
moment. :-)

I have played at least 20 CDs start to finish in the thing now and have left
it running overnight on an 80 minute disc. The power went out last night,
but this morning the player had the track list and total runtime on its
display. I've "played the drums" on the top and sides, and twiddled all the
around inside while it was playing. No change, although the pounding did
make it skip, but that's to be expected.

I'd like to think that it's fixed, but I will keep an eye on it. Why it ever
broke I guess I will probably never know. Apart from the fact that it was
soaking wet when I got it home, it doesn't look to have ever had anyone
twiddling around inside or as though it has been abused.

http://greyghost.dyndns.org/av/DSC02080.JPG (150+ KB, doesn't "do it
justice"...but if you're curious...)

William

Units exposed to water can have all sorts of weird problems occur,
especially in electromechanical devices like cd players where there are
very fine tolerances. Impurities deposited by the water , grit etc. can
find their way into connectors, transformers , and almost all other
places. If the unit is left as-is, corrosion and other problems can set
in.

Faults can take time to appear, even when the player has been dry for
considerable time. I have found that dismantling the device totally (as
soon as you get it away from the damp before rust sets in!), drying,
re-lubing, checking all areas for deposits and cleaning can minimize
the risk of problems. As you have found, reseating connectors is at
least a good place to start!

-
Ben

Hi!

Units exposed to water can have all sorts of weird problems occur,
especially in electromechanical devices like cd players where there are
very fine tolerances.

You don't say. :-) I recently had a major sewer failure cause a backup of
water into my basement. Nearly none of the CD-ROM or DVD-ROM drives that
went under remain functional. It seems that the oldest drives took it a lot
better (and held up to being cleaned in a much better way) than did any of
the new ones. The drives run and "try to work" but I think that things
inside the laser pickup got dirty when the water came along. I don't really
know how to take laser pickups apart, if it can even be done. (And I have no
desire to accidentally fry my eyes if the pickup were not to be quite
correctly put back together.)

Impurities deposited by the water , grit etc. can
find their way into connectors, transformers , and almost all other
places. If the unit is left as-is, corrosion and other problems can set
in.

This player was just set out in the trash, along with some computer monitors
and a VCR. All of them were rained on, but the CD player and VCR were still
mostly dry inside. The only places I found water in either one was around
the openings on the case.

Needless to say I mopped it all up and used gentle heat to encourage drying
of components. It didn't look like any transformers had taken a "hit".

Faults can take time to appear, even when the player has been dry for
considerable time.

Perhaps so. I haven't seen that effect myself--it has been my experience
that if the device is cleaned up and dried out promptly that its chances of
surviving are really pretty good. As it stands now I have played nearly my
entire CD collection in this thing multiple times and it remains rock solid.
I am going to hope for now that the connections had simply become marginal
(this player is not exactly new) and that my reinserting them cleaned them
enough to allow proper operations. If the player breaks again--I'll fix it
if it is feasible to do so.

I really think that the issue could have been one with a grounding contact.
I have heard of electronics acting strangely when the grounds are not
working for some reason.

I have found that dismantling the device totally (as
soon as you get it away from the damp before rust sets in!), drying,
re-lubing, checking all areas for deposits and cleaning can minimize
the risk of problems.

Indeed. I am very reluctant to grease or lubricate anything unless the
material is clearly contaminated or I'm dealing with a fan. (Fans of all
sorts, it would seem, act rather badly after they have been wet.) What
lubricating material I can see in this player looks to be good, well
distributed and not at all dirty.

Given that it was picked up from a "high income" part of town and the fact
that it is in nice condition, I'd say it lived a very nice and calm life
until its owner found that it would no longer play CDs properly. Then out
the door it went. Happens more often in that part of town than I'd care to
talk about it. I've gotten a lot of really nice stuff just by waiting for
trash day and then picking up whatever I find interesting. TV
sets...Microwaves...whole computer systems (including some very modern
ones)...misc stuff...

I think that fully 90% of what I pick up could be resold for profit, but
I've never done it that. What I can't use I give to others who need it more
than I do. I find this kind of thing to be fun...and I think in my own
little way that I'm saving the world from one more piece of equipment flying
into an already overburdened landfill.

As you have found, reseating connectors is at
least a good place to start!

It should have been the first thing that I did, but it was the last thing I
expected given that it looked like the player had been well cared for and
everything inside seemed to be in place. I think a lot of us could say that
in regards to some things we have repaired! :-)

William

"William R. Walsh" writes:

Hi!

Units exposed to water can have all sorts of weird problems occur,
especially in electromechanical devices like cd players where there are
very fine tolerances.

You don't say. :-) I recently had a major sewer failure cause a backup of
water into my basement. Nearly none of the CD-ROM or DVD-ROM drives that
went under remain functional. It seems that the oldest drives took it a lot
better (and held up to being cleaned in a much better way) than did any of
the new ones. The drives run and "try to work" but I think that things
inside the laser pickup got dirty when the water came along. I don't really
know how to take laser pickups apart, if it can even be done. (And I have no
desire to accidentally fry my eyes if the pickup were not to be quite
correctly put back together.)

The safety risk is minimal. It's more an inssue of if it's even possible to
disassemble without totally messing up the alignment, breaking tiny wires,
etc. Almost any contamination on the optical surfaces will cause the
pickup to either not work at all or have degraded performance.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

William R. Walsh wrote:
(snip)
Given that it was picked up from a "high income" part of town and the
fact
that it is in nice condition, I'd say it lived a very nice and calm
life
until its owner found that it would no longer play CDs properly. Then
out
the door it went. Happens more often in that part of town than I'd
care to
talk about it. I've gotten a lot of really nice stuff just by waiting
for
trash day and then picking up whatever I find interesting. TV
sets...Microwaves...whole computer systems (including some very
modern
ones)...misc stuff...

I think there was a thread on a subject ike this in alt.dumpster-diving
(or similar) a few years ago. amazing what you can find. More amazing
(and worrying) is how people are prepared to just toss stuff, too.

I think that fully 90% of what I pick up could be resold for profit,
but
I've never done it that. What I can't use I give to others who need
it more
than I do.

My parents-in-law have a house in the country fully kitted out with
lamps, stereos, microwaves, clock radios, TVs/VCRs in all rooms, etc.
purely thru' my scavenging/repairing, from years back!

I find this kind of thing to be fun...and I think in my own
little way that I'm saving the world from one more piece of equipment
flying
into an already overburdened landfill.

Hear hear. I think it's also a great way of learning if you approach
the repair task with an open mind and try to understand as well as just
"fix". I have made many a good find in the street, although I don't
often have the time to go hunting as much these days.

regards, Ben

wrote in message
oups.com...

| My parents-in-law have a house in the country fully kitted out with
| lamps, stereos, microwaves, clock radios, TVs/VCRs in all rooms, etc.
| purely thru' my scavenging/repairing, from years back!

Do pass the word around about http://freecycle.org/

"The worldwide FreecycleT Network is made up of many individual groups
across the globe. It's a grassroots movement of people who are giving (&
getting) stuff for free in their own towns. Each local group is run by a
local volunteer moderator (them's good people). ...

One main rule: Everything posted must be free, legal, and appropriate for
all ages. ... "

N