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From: Arfa Daily on 3 Jan 2010 05:46

"Fin West" <FW(a)nosuch.com> wrote in message
news:3b80k55fs9lncps2el2kknd99r21phm63n(a)4ax.com...
> "Arfa Daily" <arfa.daily(a)ntlworld.com> wrote:
>
>>
>>"Fin West" <FW(a)nosuch.com> wrote in message
>>news:fplvj5hr4pk62640v80ik2filkuadalv4o(a)4ax.com...
>>>I have a Teac CD-P1260 CD player that has had very little use and no
>>> abuse, and now doesn't play. It was bought 2 1/2 years ago, placed in
>>> an equipment closet and not moved until now, and has been used about
>>> 10 hours. Now it shows No Disc for any discs we try to play.
>>>
>>> I removed the cover and cleaned the lens. On inserting a disc I saw
>>> the disc clamp into place but it doesn't rotate. Everything moves
>>> freely and looks very clean.
>>>
>>> Last week I tried tapping the main circuit board, and when I did the
>>> disc started playing. When I tapped the drive itself, that also
>>> started the player working. Each time I tried another disc I had to
>>> tap again to get the player started.
>>>
>>> I had to stop working on the player until today. Today tapping doesn't
>>> work anymore. It looks like the player doesn't see a reflected light
>>> signal and won't spin the disc.
>>>
>>> Does anyone here have experience with this model player to know if
>>> this is a common problem and where to look? I would also appreciate
>>> suggestions from anyone with experience to suggest how I should
>>> proceed to try to find what's wrong.
>>>
>>
>>It may still be a dirty laser - but not where you can see it. Although the
>>lens may look clean (was it dusty before you cleaned it ??) you could have
>>dust on the CA mirror or pickup photodiode array, both of which are inside
>>the body of the laser. Another thing to try is to spin the disc with a
>>finger just after it clamps. Sometimes, lack of use can lead to a spindle
>>motor which is reluctant to start up on its own. Make sure that the laser
>>is
>>free to move on its slides. With the unit switched off and no disc in,
>>move
>>the laser by hand, away from the centre 'home' position, then power on and
>>make sure that the laser returns home, then burns (do not look directly
>>into
>>the top of the laser - observe at a shallow angle and you should be able
>>to
>>see a dull red glow in the lens) and that focus search takes place
>>correctly. The lens should move up and down probably three times, and in a
>>very 'positive' fashion. If all of this seems to take place correctly,
>>reinsert a disc. It might just play now ... (honest!)
>>
>>If it doesn't play, you can try pressing on the main pcb with a biro pen
>>or
>>some other insulated 'stick' whilst inserting a disc, and also poking the
>>laser flexiprint with the tip of a small screwdriver. Other than this,
>>without detailed knowledge of how a CD player works, and some decent test
>>equipment, you are unlikely to get far. I would say that it would be worth
>>trying a laser in it, although tap sensitivity is not generally considered
>>as a typical laser problem, but that aspect of your observations prior to
>>the total failure might be a bit of a red herring. It is of course easy
>>for
>>an engineer to say "try a laser in it", as we have them in stock on the
>>shelf (it's probably a Sony KSS 213 series laser), but I wouldn't
>>recommend
>>that you waste your money on buying a replacement, on the offchance that
>>might cure it ...
>>
>>Arfa
>>
>
> Thank you for this reply. The lens looked clean as could be before I
> cleaned it with alcohol. It looked the same after I cleaned it. I did
> spin the disc after it clamped and it spins freely and coasts a little
> before it stops. I also did move the laser by hand and watched it
> scurry back to its home position when I turned the power on. I didn't
> think I could see the lens in its home position. Tomorrow I'll try to
> observe the laser as you said.
>
> I'll continue to try poking to see if I can find something repeatable.
> I spent my entire work career in the electronics field and have many
> years experience in the design, development and troubleshooting of
> electronic equipment. While I worked I had access to all kinds of test
> equipment, but now that I'm retired the only equipment I have is a
> Heathkit VOM I built 50 years ago (it still works well). The laser is
> a Sony laser but it may be difficult for me to replace it at home.
>

OK. Most of the Teac lasers are not too difficult to replace, but I seem to
recall one or two that are bitches to get at. That said, if you are able to
see the lens and move the laser and spin the disc, this is probably one of
the easy ones (I see so many different players passing across my bench that
I don't take much notice of specific model numbers unless I need to get
service info out). If it is a Sony laser, it will (probably) use a single
white flexiprint for its connection, and have a small label at the top right
corner of its connector board which will say "KSS213C or B". There are "D",
"E" and "F" versions commonly available as well, but for most players, it is
critical to use what was originally fitted. B's and C's are very cheap. The
others a little more expensive.

Sometimes, you can remove the disc clamp bracket from a deck, which then
gives free access to the whole sub-deck. I have a sawn-off piece of an old
disc that I use to hold over the top of the lens at turntable height. You
have to be fairly accurate with the height that you are holding it at, and
hold it as level as you can, but by using this technique, you can often
'catch' the lens as it does its focus search. It will then 'hang' (as though
by magic !) a couple of mm from the underside of the disc fragment, and if
you move that fragment up and down a small amount, you can watch the lens
'follow'. If you can get the laser to obtain and hold focus like this, it's
often a good indicator that the laser is ok, and that the problem lies
elsewhere.

Arfa


From: William Sommerwerck on 3 Jan 2010 04:36
>> Sounds like a cold solder joint.

> Or a shorted spindle motor...

Perhaps, but why would tapping the main board relieve the short?


From: Arfa Daily on 3 Jan 2010 12:27

"William Sommerwerck" <grizzledgeezer(a)comcast.net> wrote in message
news:hhpvem$4g8$1(a)news.eternal-september.org...
>>> Sounds like a cold solder joint.
>
>> Or a shorted spindle motor...
>
> Perhaps, but why would tapping the main board relieve the short?
>
>

You are perhaps taking the term "shorted" too literally, William.

Clearly, it wouldn't, as such. But you will note that the OP said that it
also started working when he tapped the deck. The shorts that you get on
spindle motors are not usually 'dead shorts' because of burnt windings etc.
Rather, they are often caused by commutator contamination, which can be
severe enough to make the driver IC run 'red hot', but not enough to blow
fuses. This situation is often relieved (temporarily) by giving the motor a
nudge to help it on its way, and sometimes, that nudge need only be a
vibrational shock, such as tapping in the area. Also, the bearings sometimes
tighten up on these motors to the point where they struggle to have enough
torque to get over the stickiness - particularly if there is the added
weight of a disc on the turntable. Again, sometimes all that is needed is a
bit of a knock to get it going, and it will then be fine until next time ...

Arfa


From: William Sommerwerck on 3 Jan 2010 10:36
>> Perhaps, but why would tapping the main board relieve the short?

> You are perhaps taking the term "shorted" too literally, William.

> Clearly, it wouldn't, as such. But you will note that the OP said that it
> also started working when he tapped the deck. The shorts that you get on
> spindle motors are not usually 'dead shorts' because of burnt windings
> etc. Rather, they are often caused by commutator contamination, which
> can be severe enough to make the driver IC run 'red hot', but not enough
> to blow fuses. This situation is often relieved (temporarily) by giving
> the motor a nudge to help it on its way, and sometimes, that nudge need
> only be a vibrational shock, such as tapping in the area. Also, the
> bearings sometimes tighten up on these motors to the point where they
> struggle to have enough torque to get over the stickiness -- particularly
> if there is the added weight of a disc on the turntable. Again, sometimes
> all that is needed is a bit of a knock to get it going, and it will then
> be fine until next time.
....

I was right about the ReVox tape sensor. I would /like/ to think I'm on a
roll... <grin>





From: Mark Zacharias on 3 Jan 2010 20:20
"Arfa Daily" <arfa.daily(a)ntlworld.com> wrote in message
news:es40n.22779$PV.11883(a)newsfe19.ams2...
>
> "William Sommerwerck" <grizzledgeezer(a)comcast.net> wrote in message
> news:hhpvem$4g8$1(a)news.eternal-september.org...
>>>> Sounds like a cold solder joint.
>>
>>> Or a shorted spindle motor...
>>
>> Perhaps, but why would tapping the main board relieve the short?
>>
>>
>
> You are perhaps taking the term "shorted" too literally, William.
>
> Clearly, it wouldn't, as such. But you will note that the OP said that it
> also started working when he tapped the deck. The shorts that you get on
> spindle motors are not usually 'dead shorts' because of burnt windings
> etc. Rather, they are often caused by commutator contamination, which can
> be severe enough to make the driver IC run 'red hot', but not enough to
> blow fuses. This situation is often relieved (temporarily) by giving the
> motor a nudge to help it on its way, and sometimes, that nudge need only
> be a vibrational shock, such as tapping in the area. Also, the bearings
> sometimes tighten up on these motors to the point where they struggle to
> have enough torque to get over the stickiness - particularly if there is
> the added weight of a disc on the turntable. Again, sometimes all that is
> needed is a bit of a knock to get it going, and it will then be fine until
> next time ...
>
> Arfa
>

What he said.

Mark Z.

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