sci.electronics.repair - 25 new messages in 9 topics - digest

sci.electronics.repair
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Today's topics:

==============================================================================
TOPIC: Q: Replacing the blu-ray Laser Diode of a PS3
http://groups.google.com/group/sci.electronics.repair/t/1cac3505fd4eb852?hl=en
==============================================================================

== 1 of 7 ==
Date: Thurs, Oct 14 2010 12:48 am
From: "Arfa Daily"

"Nick Fielding" <nfielding@gmail.com> wrote in message
news:2c8a1cce-a1a7-4381-9f89-e2ca7a12bc02@s19g2000vbr.googlegroups.com...
> Hello,
>
> I'm trying to figure out how to replace a laser diode inside a ps3 blu-
> ray drive. I think I now know the best way to extract the diode.
>
> My problem is installing the new diode; I have read in several places
> that it's not simply a case of whacking the new one in, it has to be
> aligned? Is this true, and if so, what would be the best way to go
> about aligning it? How much is it likely to have to be rotated, i.e.
> fractions of a degree or larger? I don't see that it can be rotated
> that much as its degree of rotation would be limited by the flex cable
> it's soldered to.
>
> Many thanks for any help!
> Nick

I've got a colleague who replaces many PS3 laser assemblies (I take it you
are referring to the optical head which runs on the deck within the drive,
not the *actual* laser diode ?) I will ask him what is necessary. Note also
that I think I recall him saying that there are two if not three different
variants, so make sure you get the right one. I have dismantled a number of
these drives to remove discs from PS3s suffering the YLOD condition. Be
careful when you replace the drive's top plate, as several bits of disc
handling mech, have to engage correctly with other bits on the main body of
the drive. Note also that once the top cover is removed, exposing the top
mech plate of the drive, the disc clamp just lifts away. It is not retained
by anything other than being 'sandwiched' between the mech plate and the
cover. When reassembling, it just sits on top of the (should be at that
point closed) lifter 'scissors'.

Arfa

== 2 of 7 ==
Date: Thurs, Oct 14 2010 2:22 am
From: Nick Fielding

On Oct 13, 2:38 pm, "William Sommerwerck" <grizzledgee...@comcast.net>
wrote:
> If the unit is well-designed, there should be no need to do anything more
> than solder it in place.
>
> However, it's likely you'll have to perform a drive-current adjustment. This
> might require a special test disk and/or test equipment. The service manual
> should fill you in.

Thanks, I've never really thought about it this way. The unit would
have to be designed in a way to make it quick to assemble and I think
it would slow things down far too much on the production line if they
had to align the laser on each unit. Also, the laser diode for this
drive is a Sony patent and is designed for this laser assembly only so
I'm guessing a drive-current adjustment won't be required either.

Thanks again for taking the time to reply.
Nick

== 3 of 7 ==
Date: Thurs, Oct 14 2010 2:27 am
From: Nick Fielding

On Oct 14, 8:48 am, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
> "Nick Fielding" <nfield...@gmail.com> wrote in message
>
> news:2c8a1cce-a1a7-4381-9f89-e2ca7a12bc02@s19g2000vbr.googlegroups.com...
>
> > Hello,
>
> > I'm trying to figure out how to replace a laser diode inside a ps3 blu-
> > ray drive. I think I now know the best way to extract the diode.
>
> > My problem is installing the new diode; I have read in several places
> > that it's not simply a case of whacking the new one in, it has to be
> > aligned? Is this true, and if so, what would be the best way to go
> > about aligning it? How much is it likely to have to be rotated, i.e.
> > fractions of a degree or larger? I don't see that it can be rotated
> > that much as its degree of rotation would be limited by the flex cable
> > it's soldered to.
>
> > Many thanks for any help!
> > Nick
>
> I've got a colleague who replaces many PS3 laser assemblies (I take it you
> are referring to the optical head which runs on the deck within the drive,
> not the *actual* laser diode ?) I will ask him what is necessary. Note also
> that I think I recall him saying that there are two if not three different
> variants, so make sure you get the right one. I have dismantled a number of
> these drives to remove discs from PS3s suffering the YLOD condition. Be
> careful when you replace the drive's top plate, as several bits of disc
> handling mech, have to engage correctly with other bits on the main body of
> the drive. Note also that once the top cover is removed, exposing the top
> mech plate of the drive, the disc clamp just lifts away. It is not retained
> by anything other than being 'sandwiched' between the mech plate and the
> cover. When reassembling, it just sits on top of the (should be at that
> point closed) lifter 'scissors'.
>
> Arfa

Hi Arfa,

Thankyou for taking the time to reply but it's the laser diode itself
I'm working on replacing. I can replace the laser assembly no problem,
however, it's not at all economical given the price of a laser
assembly so am trying to see if I can refurbish broken assemblies by
replacing the laser diode. :)

Thanks,
Nick

== 4 of 7 ==
Date: Thurs, Oct 14 2010 3:32 am
From: "Arfa Daily"

"Nick Fielding" <nfielding@gmail.com> wrote in message
news:febc414c-e9e6-4778-9464-0775fa5d7ea2@26g2000yqv.googlegroups.com...
> On Oct 14, 8:48 am, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
>> "Nick Fielding" <nfield...@gmail.com> wrote in message
>>
>> news:2c8a1cce-a1a7-4381-9f89-e2ca7a12bc02@s19g2000vbr.googlegroups.com...
>>
>> > Hello,
>>
>> > I'm trying to figure out how to replace a laser diode inside a ps3 blu-
>> > ray drive. I think I now know the best way to extract the diode.
>>
>> > My problem is installing the new diode; I have read in several places
>> > that it's not simply a case of whacking the new one in, it has to be
>> > aligned? Is this true, and if so, what would be the best way to go
>> > about aligning it? How much is it likely to have to be rotated, i.e.
>> > fractions of a degree or larger? I don't see that it can be rotated
>> > that much as its degree of rotation would be limited by the flex cable
>> > it's soldered to.
>>
>> > Many thanks for any help!
>> > Nick
>>
>> I've got a colleague who replaces many PS3 laser assemblies (I take it
>> you
>> are referring to the optical head which runs on the deck within the
>> drive,
>> not the *actual* laser diode ?) I will ask him what is necessary. Note
>> also
>> that I think I recall him saying that there are two if not three
>> different
>> variants, so make sure you get the right one. I have dismantled a number
>> of
>> these drives to remove discs from PS3s suffering the YLOD condition. Be
>> careful when you replace the drive's top plate, as several bits of disc
>> handling mech, have to engage correctly with other bits on the main body
>> of
>> the drive. Note also that once the top cover is removed, exposing the top
>> mech plate of the drive, the disc clamp just lifts away. It is not
>> retained
>> by anything other than being 'sandwiched' between the mech plate and the
>> cover. When reassembling, it just sits on top of the (should be at that
>> point closed) lifter 'scissors'.
>>
>> Arfa
>
> Hi Arfa,
>
> Thankyou for taking the time to reply but it's the laser diode itself
> I'm working on replacing. I can replace the laser assembly no problem,
> however, it's not at all economical given the price of a laser
> assembly so am trying to see if I can refurbish broken assemblies by
> replacing the laser diode. :)
>
> Thanks,
> Nick

In that case, I think you will really struggle to ever get it working again.
The laser diode is an *extremely* precision fit in the optics, aligned at
the factory in a precision jig. I once experimented with this on CD lasers,
with just about zero success. Even if I got it to read again, the
playability was poor. Ask anyone who has ever replaced a Pioneer laser just
how difficult it is to align the diffraction grating. Gnat's bollock
precision doesn't begin to describe how difficult it is to get it right, and
that's Grand Canyon versus an alleyway in terms of relative data pit size.

Given that CD optics are 'broken leg' technology, then DVD optics are in
'heart transplant' territory. Blu Ray, as PS3 lasers are, then fall into
'brain surgery' by comparison ... If the laser diode is even a vanishingly
tiny amount off-axis, the beams will not pass through the centre of the
lens, so the chances of them being reflected back from the disc correctly to
hit the pickup diodes are, IMHO, poor at best. Bear in mind also, that it is
not necessarily the laser diode that is at fault. Problems with laser
assemblies can also be down to contaminated optics - i.e. nicotine on the
critical angle mirror - a faulty pickup diode assembly, or faulty tracking /
focus coils.

I am surprised that you think that the cost of a replacement optical
assembly warrants attempting to do it by this method. According to my oppo,
the price of replacement optical heads is quite reasonable, and allows a
good margin on the job ...

You might like to look at Sam's stuff on these heads at

http://www.repairfaq.org/sam/Blu-ray/site1/optics.html

and also the material at

http://www.optoiq.com/index/photonics-technologies-applications/lfw-display/lfw-article-display/352182/articles/laser-focus-world/volume-45/issue-2/features/diffractive-optics-harmonic-optical-element-simplifies-blu-ray-optics.html

which will give you a bit more of an insight into how much precision is
involved in these assemblies.

Arfa

== 5 of 7 ==
Date: Thurs, Oct 14 2010 4:54 am
From: Nick Fielding

On Oct 14, 11:32 am, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
> "Nick Fielding" <nfield...@gmail.com> wrote in message
>
> news:febc414c-e9e6-4778-9464-0775fa5d7ea2@26g2000yqv.googlegroups.com...
>
>
>
>
>
> > On Oct 14, 8:48 am, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
> >> "Nick Fielding" <nfield...@gmail.com> wrote in message
>
> >>news:2c8a1cce-a1a7-4381-9f89-e2ca7a12bc02@s19g2000vbr.googlegroups.com...
>
> >> > Hello,
>
> >> > I'm trying to figure out how to replace a laser diode inside a ps3 blu-
> >> > ray drive. I think I now know the best way to extract the diode.
>
> >> > My problem is installing the new diode; I have read in several places
> >> > that it's not simply a case of whacking the new one in, it has to be
> >> > aligned? Is this true, and if so, what would be the best way to go
> >> > about aligning it? How much is it likely to have to be rotated, i.e.
> >> > fractions of a degree or larger? I don't see that it can be rotated
> >> > that much as its degree of rotation would be limited by the flex cable
> >> > it's soldered to.
>
> >> > Many thanks for any help!
> >> > Nick
>
> >> I've got a colleague who replaces many PS3 laser assemblies (I take it
> >> you
> >> are referring to the optical head which runs on the deck within the
> >> drive,
> >> not the *actual* laser diode ?) I will ask him what is necessary. Note
> >> also
> >> that I think I recall him saying that there are two if not three
> >> different
> >> variants, so make sure you get the right one. I have dismantled a number
> >> of
> >> these drives to remove discs from PS3s suffering the YLOD condition. Be
> >> careful when you replace the drive's top plate, as several bits of disc
> >> handling mech, have to engage correctly with other bits on the main body
> >> of
> >> the drive. Note also that once the top cover is removed, exposing the top
> >> mech plate of the drive, the disc clamp just lifts away. It is not
> >> retained
> >> by anything other than being 'sandwiched' between the mech plate and the
> >> cover. When reassembling, it just sits on top of the (should be at that
> >> point closed) lifter 'scissors'.
>
> >> Arfa
>
> > Hi Arfa,
>
> > Thankyou for taking the time to reply but it's the laser diode itself
> > I'm working on replacing. I can replace the laser assembly no problem,
> > however, it's not at all economical given the price of a laser
> > assembly so am trying to see if I can refurbish broken assemblies by
> > replacing the laser diode. :)
>
> > Thanks,
> > Nick
>
> In that case, I think you will really struggle to ever get it working again.
> The laser diode is an *extremely* precision fit in the optics, aligned at
> the factory in a precision jig. I once experimented with this on CD lasers,
> with just about zero success. Even if I got it to read again, the
> playability was poor. Ask anyone who has ever replaced a Pioneer laser just
> how difficult it is to align the diffraction grating. Gnat's bollock
> precision doesn't begin to describe how difficult it is to get it right, and
> that's Grand Canyon versus an alleyway in terms of relative data pit size.
>
> Given that CD optics are 'broken leg' technology, then DVD optics are in
> 'heart transplant' territory. Blu Ray, as PS3 lasers are, then fall into
> 'brain surgery' by comparison ... If the laser diode is even a vanishingly
> tiny amount off-axis, the beams will not pass through the centre of the
> lens, so the chances of them being reflected back from the disc correctly to
> hit the pickup diodes are, IMHO, poor at best. Bear in mind also, that it is
> not necessarily the laser diode that is at fault. Problems with laser
> assemblies can also be down to contaminated optics - i.e. nicotine on the
> critical angle mirror - a faulty pickup diode assembly, or faulty tracking /
> focus coils.
>
> I am surprised that you think that the cost of a replacement optical
> assembly warrants attempting to do it by this method. According to my oppo,
> the price of replacement optical heads is quite reasonable, and allows a
> good margin on the job ...
>
> You might like to look at Sam's stuff on these heads at
>
> http://www.repairfaq.org/sam/Blu-ray/site1/optics.html
>
> and also the material at
>
> http://www.optoiq.com/index/photonics-technologies-applications/lfw-d...
>
> which will give you a bit more of an insight into how much precision is
> involved in these assemblies.
>
> Arfa- Hide quoted text -
>
> - Show quoted text -

That does indeed look like it requires a lot of precision.

A lens assembly costs upwards of £25 whereas a replacement laser diode
for the 410aca blu-ray drive I can get for £7. Obviously replacing the
laser diode is a fiddly and by the looks of it impossible job;
although there are people out there who are managing to do it, maybe
they have their own jig or something.

I'll probably give it a go and fail.

Many Thanks,
Nick

== 6 of 7 ==
Date: Thurs, Oct 14 2010 5:42 am
From: "William Sommerwerck"

>> If the unit is well-designed, there should be no need to do anything
>> more than solder it in place.

>> However, it's likely you'll have to perform a drive-current adjustment.
>> This might require a special test disk and/or test equipment. The
>> service manual should fill you in.

> Thanks, I've never really thought about it this way. The unit would
> have to be designed in a way to make it quick to assemble and I think
> it would slow things down far too much on the production line if they
> had to align the laser on each unit. Also, the laser diode for this
> drive is a Sony patent and is designed for this laser assembly only so
> I'm guessing a drive-current adjustment won't be required either.

Actually, I would go with what Arfa says. What I said was "common sense" --
but probably isn't correct.

With respect to production lines... It isn't how "difficult" it is to do
something -- especially if the difficulty is reduced by the use of custom
fixtures and test equipment -- but by how long it takes. One of the reasons
"modern" electronic equipment is so much cheaper is a high level of
integration (ie, fewer parts) combined with much less human labor. And if
you can get that labor Really Cheap overseas, so much the better.

I do, however, find it hard to believe that laser-diode installation requres
extremely precise adjustments. This (to me) indicates poor product design.
Of course, I'm not omniscient in such matters.

== 7 of 7 ==
Date: Thurs, Oct 14 2010 6:22 am
From: "Arfa Daily"

"Nick Fielding" <nfielding@gmail.com> wrote in message
news:becf8e9c-b416-4941-adbd-db8076ff1c34@c16g2000vbp.googlegroups.com...
> On Oct 14, 11:32 am, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
>> "Nick Fielding" <nfield...@gmail.com> wrote in message
>>
>> news:febc414c-e9e6-4778-9464-0775fa5d7ea2@26g2000yqv.googlegroups.com...
>>
>>
>>
>>
>>
>> > On Oct 14, 8:48 am, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
>> >> "Nick Fielding" <nfield...@gmail.com> wrote in message
>>
>> >>news:2c8a1cce-a1a7-4381-9f89-e2ca7a12bc02@s19g2000vbr.googlegroups.com...
>>
>> >> > Hello,
>>
>> >> > I'm trying to figure out how to replace a laser diode inside a ps3
>> >> > blu-
>> >> > ray drive. I think I now know the best way to extract the diode.
>>
>> >> > My problem is installing the new diode; I have read in several
>> >> > places
>> >> > that it's not simply a case of whacking the new one in, it has to be
>> >> > aligned? Is this true, and if so, what would be the best way to go
>> >> > about aligning it? How much is it likely to have to be rotated, i.e.
>> >> > fractions of a degree or larger? I don't see that it can be rotated
>> >> > that much as its degree of rotation would be limited by the flex
>> >> > cable
>> >> > it's soldered to.
>>
>> >> > Many thanks for any help!
>> >> > Nick
>>
>> >> I've got a colleague who replaces many PS3 laser assemblies (I take it
>> >> you
>> >> are referring to the optical head which runs on the deck within the
>> >> drive,
>> >> not the *actual* laser diode ?) I will ask him what is necessary. Note
>> >> also
>> >> that I think I recall him saying that there are two if not three
>> >> different
>> >> variants, so make sure you get the right one. I have dismantled a
>> >> number
>> >> of
>> >> these drives to remove discs from PS3s suffering the YLOD condition.
>> >> Be
>> >> careful when you replace the drive's top plate, as several bits of
>> >> disc
>> >> handling mech, have to engage correctly with other bits on the main
>> >> body
>> >> of
>> >> the drive. Note also that once the top cover is removed, exposing the
>> >> top
>> >> mech plate of the drive, the disc clamp just lifts away. It is not
>> >> retained
>> >> by anything other than being 'sandwiched' between the mech plate and
>> >> the
>> >> cover. When reassembling, it just sits on top of the (should be at
>> >> that
>> >> point closed) lifter 'scissors'.
>>
>> >> Arfa
>>
>> > Hi Arfa,
>>
>> > Thankyou for taking the time to reply but it's the laser diode itself
>> > I'm working on replacing. I can replace the laser assembly no problem,
>> > however, it's not at all economical given the price of a laser
>> > assembly so am trying to see if I can refurbish broken assemblies by
>> > replacing the laser diode. :)
>>
>> > Thanks,
>> > Nick
>>
>> In that case, I think you will really struggle to ever get it working
>> again.
>> The laser diode is an *extremely* precision fit in the optics, aligned at
>> the factory in a precision jig. I once experimented with this on CD
>> lasers,
>> with just about zero success. Even if I got it to read again, the
>> playability was poor. Ask anyone who has ever replaced a Pioneer laser
>> just
>> how difficult it is to align the diffraction grating. Gnat's bollock
>> precision doesn't begin to describe how difficult it is to get it right,
>> and
>> that's Grand Canyon versus an alleyway in terms of relative data pit
>> size.
>>
>> Given that CD optics are 'broken leg' technology, then DVD optics are in
>> 'heart transplant' territory. Blu Ray, as PS3 lasers are, then fall into
>> 'brain surgery' by comparison ... If the laser diode is even a
>> vanishingly
>> tiny amount off-axis, the beams will not pass through the centre of the
>> lens, so the chances of them being reflected back from the disc correctly
>> to
>> hit the pickup diodes are, IMHO, poor at best. Bear in mind also, that it
>> is
>> not necessarily the laser diode that is at fault. Problems with laser
>> assemblies can also be down to contaminated optics - i.e. nicotine on the
>> critical angle mirror - a faulty pickup diode assembly, or faulty
>> tracking /
>> focus coils.
>>
>> I am surprised that you think that the cost of a replacement optical
>> assembly warrants attempting to do it by this method. According to my
>> oppo,
>> the price of replacement optical heads is quite reasonable, and allows a
>> good margin on the job ...
>>
>> You might like to look at Sam's stuff on these heads at
>>
>> http://www.repairfaq.org/sam/Blu-ray/site1/optics.html
>>
>> and also the material at
>>
>> http://www.optoiq.com/index/photonics-technologies-applications/lfw-d...
>>
>> which will give you a bit more of an insight into how much precision is
>> involved in these assemblies.
>>
>> Arfa- Hide quoted text -
>>
>> - Show quoted text -
>
>
> That does indeed look like it requires a lot of precision.
>
> A lens assembly costs upwards of £25 whereas a replacement laser diode
> for the 410aca blu-ray drive I can get for £7. Obviously replacing the
> laser diode is a fiddly and by the looks of it impossible job;
> although there are people out there who are managing to do it, maybe
> they have their own jig or something.
>
> I'll probably give it a go and fail.
>
> Many Thanks,
> Nick

As for people claiming to be able to do this job, treat the claims with
caution. There are many people offering 'guaranteed solutions' to for
instance the YLOD problem, and indeed they do appear to work - at least
initially. The trick is that they only seem to last long enough to dispose
of the unit claiming it to be a 'worker' ...

The minimum independant commercial repair cost for a PS3 is around 80 quid.
My friend charges £120 to replace a laser, and he has no shortage of takers.
Sony charge 180 quid for a service exchange PS3, and the cost of a new (pre
latest slimline version) PS3 is around £300. Non-workers go on eBay for
anything up to £90, and working examples for a lot more than that, so I
think that there is potentially enough margin in laser replacement to
warrant not having to mess around trying to repair the laser assembly -
given that the bulk of the cost is the labour you will have already put in
to strip the PS3 and its drive. and then remove the laser anyway to attempt
the diode replacement ....

Don't forget to be careful not to lose the little bent piece of metal that
the Torx screw that holds the top cover goes into. Only valid for Mk1's of
course, the screw going into a moulding on Mk2's and 3's.

Good luck. If you do attempt it, do let us know (honestly !!) how it goes,
as I am an interested party on PS3 repairs.

Arfa

==============================================================================
TOPIC: sgc528[23] xref
http://groups.google.com/group/sci.electronics.repair/t/6861c55ad109c3a9?hl=en
==============================================================================

== 1 of 4 ==
Date: Thurs, Oct 14 2010 2:41 am
From: JW

On 14 Oct 2010 07:18:44 GMT frank <frank@not.it> wrote in Message id:
<4cb6aed4$0$6839$5fc30a8@news.tiscali.it>:

>PeterD <peter2@hipson.net> wrote:
>> On 13 Oct 2010 14:48:19 GMT, frank <frank@isntvalid.it> wrote:
>>
>>>
>>>many thanks, can I ask you where did you find these specs?
>>>
>>>Frank IZ8DWF
>>
>> Google is your friend, they were from something from (of all places)
>> Heathkit, IIRC. I just searched for the first one, got about 10 hits,
>> and only the last one (a PDF) looked interesting (most of the rest
>> were your query...)
>
>Interesting, I did a google search before posting the request to the
>newsgroup (and repeated the query right now) and it did always showed
>two or three results with no meaningful data (other than beeing used in
>heathkit equipment). No PDF either.
>I guess google can chose friends then :-)
>I'd still like to see that pdf if you can post a link please.
>Best regards.

http://www.google.com/url?sa=t&source=web&cd=6&sqi=2&ved=0CB4QFjAF&url=http%3A%2F%2Fwww.ki6yfq.com%2Fmanuals_schematics%2FHeathkit%2Fother%2Fparts_cross_reference.pdf&rct=j&q=SGC5282%20pdf&ei=OM-2TIf4FsP98Abpr6HkCQ&usg=AFQjCNG_n9_rZCHOVb2k_wtecePspaBkmg&cad=rja'

That's a long one!

== 2 of 4 ==
Date: Thurs, Oct 14 2010 3:12 am
From: frank

JW <none@dev.null> wrote:
>>
>>Interesting, I did a google search before posting the request to the
>>newsgroup (and repeated the query right now) and it did always showed
>>two or three results with no meaningful data (other than beeing used in
>>heathkit equipment). No PDF either.
>>I guess google can chose friends then :-)
>>I'd still like to see that pdf if you can post a link please.
>>Best regards.
>
> http://www.google.com/url?sa=t&source=web&cd=6&sqi=2&ved=0CB4QFjAF&url=http%3A%2F%2Fwww.ki6yfq.com%2Fmanuals_schematics%2FHeathkit%2Fother%2Fparts_cross_reference.pdf&rct=j&q=SGC5282%20pdf&ei=OM-2TIf4FsP98Abpr6HkCQ&usg=AFQjCNG_n9_rZCHOVb2k_wtecePspaBkmg&cad=rja'
>
> That's a long one!

many thanks, it's a good one to have around when repairing old HW :-)
Why I couldn't find this one with google is a mistery.

Regards
Frank IZ8DWF

== 3 of 4 ==
Date: Thurs, Oct 14 2010 5:26 am
From: JW

On 14 Oct 2010 10:12:27 GMT frank <frank@not.it> wrote in Message id:
<4cb6d78b$0$6837$5fc30a8@news.tiscali.it>:

>JW <none@dev.null> wrote:
>>>
>>>Interesting, I did a google search before posting the request to the
>>>newsgroup (and repeated the query right now) and it did always showed
>>>two or three results with no meaningful data (other than beeing used in
>>>heathkit equipment). No PDF either.
>>>I guess google can chose friends then :-)
>>>I'd still like to see that pdf if you can post a link please.
>>>Best regards.
>>
>> http://www.google.com/url?sa=t&source=web&cd=6&sqi=2&ved=0CB4QFjAF&url=http%3A%2F%2Fwww.ki6yfq.com%2Fmanuals_schematics%2FHeathkit%2Fother%2Fparts_cross_reference.pdf&rct=j&q=SGC5282%20pdf&ei=OM-2TIf4FsP98Abpr6HkCQ&usg=AFQjCNG_n9_rZCHOVb2k_wtecePspaBkmg&cad=rja'
>>
>> That's a long one!
>
>many thanks, it's a good one to have around when repairing old HW :-)
>Why I couldn't find this one with google is a mistery.
>
>Regards
>Frank IZ8DWF

I used SGC5282 pdf
or
http://www.google.com/search?hl=en&source=hp&biw=1423&bih=862&q=SGC5282+pdf&btnG=Google+Search&aq=f&aqi=&aql=&oq=&gs_rfai=CgPwu4va2TNrIEpz0ygSj2M3cCQAAAKoEBU_QUUyi

== 4 of 4 ==
Date: Thurs, Oct 14 2010 6:06 am
From: PeterD

On 14 Oct 2010 07:18:44 GMT, frank <frank@not.it> wrote:

Perhaps not from Heathkit directly (I didn't check...)

http://www.ki6yfq.com/manuals_schematics/Heathkit/other/parts_cross_reference.pdf

but dealing with Heathkit however. Big PDF, do a search in it, there
is only one reference to the parts.

==============================================================================
TOPIC: Kenwood L-1000T, 1990
http://groups.google.com/group/sci.electronics.repair/t/90eff8f4c2e643e4?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 14 2010 4:33 am
From: baron

David Inscribed thus:

> "baron" wrote in message
> news:i91jrh$810$1@news.eternal-september.org...
>
> Baron Inscribed thus:
>
>> Baron Inscribed thus:
>>
>>> David Inscribed thus:
>>>>
>>>>> I would concur with William. I have a 0.22F @ 5v on my desk
>>>>> at
>>>>> the moment, it holds its charge for many days.
>>>>>
>>>>> Best Regards:
>>>>> Baron.
>>>>
>>>> Lets get things correct here. Memory backup capacitors can
>>>> have
>>>> very high capacitance values and extremely low leakage. That
>>>> is
>>>> not in dispute. The term supercap does not refer to the
>>>> typical
>>>> memory capacitor installed on consumer electronics equipment.
>>>> That is a different type that has high series resistance. If
>>>> you
>>>> have a ESR meter, measure one for yourself but discharge it
>>>> first
>>>> for a long time.
>>>>
>>>> David
>>>
>>> Thanks for your note.
>>> Yes the cap I have is intended for memory retention service.
>>> I do
>>> have an ESR meter but it hadn't occurred to me to actually
>>> measure
>>> it,
>>> though I do take your point about discharging it first. I did
>>> discharge it some time ago and was surprised by how much the
>>> voltage
>>> had recovered the following day.
>>>
>>
>> Just and update: I got the marked value wrong, its 2.2F @ 5v.
>> There
>> is
>> no indication of the manufacturer. I've currently got a 4.5v
>> 60ma
>> torch bulb connected across it to discharge it. It took a few
>> seconds
>> for the bulb to stop glowing. Anyway I'm going to leave it
>> overnight
>> and check its ESR tomorrow. It should be well and truly
>> discharged by
>> then.
>>
>
>>Following up: The ESR measures 10-11 ohms (last digit can't
>>make up its
>>mnd). Peak charge current from a 5v 0.5ohm source hits 480ma
>>(AVO 8
>>on 1A range) before rapidly dropping to zero. Four hours later
>>the
>>terminal voltage is still 5V (Advance 10Mopv meter).
>>
>>--
>>Best Regards:
>> Baron.
>
> You have a good one with 10 ohms. The 10 - 15 year old ones had
> much higher ESR even when new but still low leakage.
>
> David

Wow ! Thanks. :-)
Apart from playing with it yesterday, its sat on my bench for weeks
looking for something to do...

--
Best Regards:
Baron.

==============================================================================
TOPIC: What should be the value of the resistance?
http://groups.google.com/group/sci.electronics.repair/t/0e24671f1705909d?hl=en
==============================================================================

== 1 of 3 ==
Date: Thurs, Oct 14 2010 5:46 am
From: "William Sommerwerck"

You need to find a book on transistor circuit design. A college-level text
should be okay. The math isn't complex, so you shouldn't have trouble
understanding it.

Hint: Since the "big" resistor is bypassed, you can model the small-signal
AC gain as if the big resistor weren't there at all. DC feedback is the sum
of both resistors, of course.

== 2 of 3 ==
Date: Thurs, Oct 14 2010 9:14 am
From: "Michael A. Terrell"

William Sommerwerck wrote:
>
> You need to find a book on transistor circuit design. A college-level text
> should be okay. The math isn't complex, so you shouldn't have trouble
> understanding it.
>
> Hint: Since the "big" resistor is bypassed, you can model the small-signal
> AC gain as if the big resistor weren't there at all. DC feedback is the sum
> of both resistors, of course.

His question looks to have been copied from a poorly written
textbook.

--
Politicians should only get paid if the budget is balanced, and there is
enough left over to pay them.

== 3 of 3 ==
Date: Thurs, Oct 14 2010 9:27 am
From: "William Sommerwerck"

>> You need to find a book on transistor circuit design. A college-level
>> text should be okay. The math isn't complex, so you shouldn't have
>> trouble understanding it.

> His question looks to have been copied from a poorly written
> textbook.

He's probably asking for someone to do his homework.

==============================================================================
TOPIC: see south star thamanna dress changing videos shooted in hidden cam
http://groups.google.com/group/sci.electronics.repair/t/4b19666b6ecfd695?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 14 2010 6:37 am
From: lucky girl

see south star thamanna dress changing videos shooted in hidden cam
At http://fingerchips.co.cc

Due to high sex security risks, i have hidden the videos(06) in an
image.
in that website on Right side below search box click on image
and watch videos in all angles.

==============================================================================
TOPIC: mis-connecting audio and composite video
http://groups.google.com/group/sci.electronics.repair/t/6df650a80c93f7fd?hl=en
==============================================================================

== 1 of 4 ==
Date: Thurs, Oct 14 2010 7:51 am
From: Ulysses

What happens (in terms of damage) if you connect an audio signal to a
composite video input or composite video to an audio input?

I have an old Sony camcorder that has single-channel audio + composite
video out from a 3.5 mm (1/8") jack. The "correct" cable has a 3.5 mm
plug one one end and a black RCA plug (audio) and a yellow RCA plug
(composite video) on the other ... and costs $17 or more.

I have a 3.5 mm to stereo RCA (red and black) audio cable. I can't see
why this cable wouldn't work, but I don't know if the black on my cable
corresponds to the black connector on the "correct" cable or to the
yellow connector. So it's possible that I may connect the audio signal
to the composite video input of my monitor. Is there a risk of damage
to the monitor?

== 2 of 4 ==
Date: Thurs, Oct 14 2010 8:36 am
From: "William Sommerwerck"

Use the cable you have. It's highly unlikely any damage will occur.

I believe audio is at a lower level than video, so try plugging the cable
into the video input first.

PS: As the audio on the expensive cable has a black plug, it's probably the
"left" channel of the stereo jack -- the "tip".

== 3 of 4 ==
Date: Thurs, Oct 14 2010 8:37 am
From: Meat Plow

On Thu, 14 Oct 2010 10:51:59 -0400, Ulysses wrote:

> What happens (in terms of damage) if you connect an audio signal to a
> composite video input or composite video to an audio input?
>
> I have an old Sony camcorder that has single-channel audio + composite
> video out from a 3.5 mm (1/8") jack. The "correct" cable has a 3.5 mm
> plug one one end and a black RCA plug (audio) and a yellow RCA plug
> (composite video) on the other ... and costs $17 or more.
>
> I have a 3.5 mm to stereo RCA (red and black) audio cable. I can't see
> why this cable wouldn't work, but I don't know if the black on my cable
> corresponds to the black connector on the "correct" cable or to the
> yellow connector. So it's possible that I may connect the audio signal
> to the composite video input of my monitor. Is there a risk of damage
> to the monitor?

Do a little research on google. I'm sure you'll find a wiring diagram of
those cables. They were pretty much standard among A/V cables. And yes
that cable will do a decent enough job for video without getting into
technical details.

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

== 4 of 4 ==
Date: Thurs, Oct 14 2010 9:59 am
From: Ulysses

On 10/14/2010 11:36 AM, William Sommerwerck wrote:
> Use the cable you have. It's highly unlikely any damage will occur.
>
> I believe audio is at a lower level than video, so try plugging the cable
> into the video input first.
>
> PS: As the audio on the expensive cable has a black plug, it's probably the
> "left" channel of the stereo jack -- the "tip".
>
>

Thanks. Yes, the black plug on the expensive cable is for the left
channel ... but on the red/white audio cable it turned out that the
white was the video and the red was the audio.

==============================================================================
TOPIC: Ryon Gambill: CON MAN
http://groups.google.com/group/sci.electronics.repair/t/f5a5353aac5d0f38?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 14 2010 8:30 am
From: Anne Onime

Ryon Gambill conducts identity theft with Experian files.

He creates debts you never owed and harasses until you pay.

He wrecks your credit until you pay him to stop.

He makes you pay through Western Union.

Enough is enough.

Call him and tell him what you think.

760 423-1100
760 423-1111

Write to his family. They need to know where the botox, ski trips, iPad, SUV and private Kenny Chesney concert money came from.

Mrs. Kim Gambill
75147 La Sierra Drive
Palm Desert
California 92211

==============================================================================
TOPIC: Driveway sensor, model 917-1, mfg. around 1993 by "Detector Systems"
http://groups.google.com/group/sci.electronics.repair/t/502c70dec1b2d85e?hl=en
==============================================================================

== 1 of 3 ==
Date: Thurs, Oct 14 2010 9:55 am
From: klem kedidelhopper

On Oct 14, 1:21 am, nesesu <neil_sutcli...@telus.net> wrote:
> On Oct 13, 8:42 pm, "hrhofm...@att.net" <hrhofm...@att.net> wrote:
>
> > How did you locate the manual?
>
> Third item shown when I Googled "Detector Systems model 917-1".
>
> Neil S.

Neil
Last night I connected about 100 feet of 2 conductor 16AWG. sheilded
cable to the test loop and ran it into the house. The sheild is
grounded on the controller end. The modified coil with three turns and
a 4 ft by 8 ft. perimeter now and a total length of approximately 72
feet is laying in the driveway.With the dip switch sensitivity
combination I found the controller seems to detect a vehicle on the
approach every time now. We're in New Hampshire so the real test will
probably come when the coil is buried and the ground is frozen with
ice and snow on top.
Thank you very much for finding and sending me that manual. The
interesting thing is that although it is indeed for a "917-1", it is
marked 3M. I guess that 3M must have bought out detector Systems and
simply put their own name on the unit. It does appear to be the same
unit as mine though.
In comparing the manual 's coil specifications to mine the manual
calls for a coil consisting of an 18" x 54" loop with 5 or 6 turns of
16AWG. cable. Therefore the total amount of wire in that coil will be
[(18+54) X 2] x 6
[(18+54) x 2] = 144
Then 144 X 6 = 864
854/ 12 = 72ft.
So it seems that although their coil uses more turns of wire, the
total wire length of theirs and my present test coil is the same. In
your opinion, what is the significance of more turns as opposed to
larger perimeter? I'm concerned of course with system reliability and
naturally repeatability. If this thing fails to detect even one time
it will be useless to us. And I certainly won't be digging it up in
January. Would I be better off with building and burying their smaller
coil with more turns or the one I'm trying out now? Thanks, Lenny.

== 2 of 3 ==
Date: Thurs, Oct 14 2010 11:50 am
From: klem kedidelhopper

== 3 of 3 ==
Date: Thurs, Oct 14 2010 11:53 am
From: klem kedidelhopper

Having trouble posting. I don't know if this is going through.
Neil
Last night I connected about 100 feet of 2 conductor 16AWG. sheilded
cable to the test loop and ran it into the house. The sheild is
grounded on the controller end. The modified coil with three turns and
a 4 ft by 8 ft. perimeter now and a total length of approximately 72
feet is laying in the driveway.With the dip switch sensitivity
combination I found the controller seems to detect a vehicle on the
approach every time now. We're in New Hampshire so the real test will
probably come when the coil is buried and the ground is frozen with
ice and snow on top.
Thank you very much for finding and sending me that manual. The
interesting thing is that although it is indeed for a "917-1", it is
marked 3M. I guess that 3M must have bought out detector Systems and
simply put their own name on the unit. It does appear to be the same
unit as mine though.
In comparing the manual 's coil specifications to mine the manual
calls for a coil consisting of an 18" x 54" loop with 5 or 6 turns of
16AWG. cable. Therefore the total amount of wire in that coil will be
[(18+54) X 2] x 6
[(18+54) x 2] = 144
Then 144 X 6 = 864
854/ 12 = 72ft.
So it seems that although their coil uses more turns of wire, the
total wire length of theirs and my present test coil is the same. In
your opinion, what is the significance of more turns as opposed to
larger perimeter? I'm concerned of course with system reliability and
naturally repeatability. If this thing fails to detect even one time
it will be useless to us. And I certainly won't be digging it up in
January. Would I be better off with building and burying their smaller
coil with more turns or the one I'm trying out now? Thanks, Lenny.

==============================================================================
TOPIC: Transistor ID...
http://groups.google.com/group/sci.electronics.repair/t/206b5827a2414f1b?hl=en
==============================================================================

== 1 of 1 ==
Date: Thurs, Oct 14 2010 11:43 am
From: PlainBill47@yawho.com

On Wed, 13 Oct 2010 14:08:51 -0700 (PDT), tmcw <tmcwboards@gmail.com>
wrote:

>Posted this at sci.electronics.basics; got redirected to here. Hope
>someone can help:
>
>Have a broken inverter on a 2000fp Dell LCD monitor.
>
>One of the transistors is visibly fried on the board.
>
>Can anyone help me ID what type of transistor it is, and where I
>could
>source a replacement?
>
>Markings on it: DT QX
>
>Q12 in the photo linked below.
>
>Photo: http://i663.photobucket.com/albums/uu357/polyfusion/2000fp_Invert.jpg
>
>Thanks.

Per http://www.s-manuals.com/smd/dt it is a Rohm 2SD2391
Sources include both Mouser and Digikey in the US, eBay in the UK, and
countless sites in the Far East.

PlainBill

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