Re: Picture Tube Hazards


"Scott" <sws2000@xxxxxxxxx> wrote in message
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Arfa Daily wrote:
"Scott" <sws2000@xxxxxxxxx> wrote in message
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Arfa Daily wrote:

You are brave to recommend these !

IMHO, if you want to do no good at all at best, and actually damage the
laser at worst, use a cleaning disc with little brushes on it ... On
several occasions, I have seen an otherwise good laser wrecked by the
brush getting caught in the lens suspension, and tearing this off with
the high rotational speed of a DVD.
Don't tell me that:( But since a laser cleaning CD kit is a 'CD'
wouldn't the DVD player use the rotational speed for a CD?

Well, once it has determined that it *is* a CD, it might, but there are a
couple of qualifiers here. Firstly, most DVD players assume a DVD first,
so spin up to full speed in readiness for that. They only then slow back
down to CD speed, once they've determined that the data streaming off the
disc is CD audio, not DVD video and audio. Secondly, some DVD players run
CDs at full speed also, much like a personal CD player runs the disc at
high speed, when in anti-shock mode ( to keep the bit bucket full ).
Thirdly, some players have a lot of trouble making any sense of a
cleaning disc. I don't know whether this is an issue with the data
contained on them, or whether it's an issue with the brushes whacking the
lens on every rotation, and vibrating it about its correct focus point.
Whatever it is anyway, some players just will not lock their spindle
servos on these discs, and they just run at very high speed, totally out
of control. At the end of the day, the only way to clean a laser lens, is
'properly' - that is by hand, carefully, with nothing more aggressive
than electronics grade IPA. Even then, any improvement may be only
marginal or temporary as, if dust on the lens was the primary cause of
whatever problem was apparent, the chances are that there is also dust on
the critical angle mirror and the face of the pickup photodiode array,
both of which are internal components of the optical block ( laser ) that
you can't get at to clean. And again, DVD lasers seldom collect dust on
their lens, due to the blanket of air dragged round under the disc, by
its high rotational speed.

Arfa

I'm definitely learning something from all this!
When I went to look up the DVD unit on Panasonic's site it tells me I
can't order through the internet, I have to call to inquire about the part
in which I figure no problem. Then when I went to this site:
http://www.orderpartsnow.com/PANASONIC-PARTS-MSC-1.asp
it tells me "AUTHORIZATION REQUIRED*. So now I'm wondering if Panasonic
need authorization also.
BTW the order number is: LSXK0140
Anyways I will attempt to clean the laser this weekend and report back.
Thanks for all your help!

-ss

You could be running into a problem here, which bugs all 'normal' Panasonic
dealers. They have two flavours of dealer, normal, and DSN, which I think
stands for "Digital Service Network". In order to become a DSN dealer, you
have to be prepared to invest thousands in test equipment and so on, so this
pretty much precludes any of us small independants, ever being able to
achieve DSN status. The real bugbear to this is that Panasonic / Technics
service, won't even speak to you, let alone give you any pointers, and
ordering any spare parts is a complete no-no, as is getting any service
info. If you go onto their website, it recognises from your logon details,
that you are not a DSN dealer, so excludes you from access to related
material. It's all so silly really. A friend of mine is a regular Pan
dealer, and they are quite happy for him to sell their 'digital' products,
but will not allow him to service them, even under warranty. Instead, they
have to go to another dealer in a town 20 odd miles away, who is authorised
to do them. As you can imagine, this goes down with the owner of an
in-warranty item, like a lead balloon. The really, really silly bit about it
all, is that in general, Panasonic do not allow even the DSN dealers to
actually do much by way of repairing the units, instead, supplying
replacement boards and drives, which any of us could block diagnose and
replace. It gets even more ludicrous when you consider that their ordinary
DVD players and hifis have no such restriction, and a normal dealer is free
to order any part or service info that he wants, to allow him to effect a
repair down to component level !

Arfa


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