Digest for sci.electronics.repair@googlegroups.com - 3 updates in 3 topics

"ohg...@gmail.com" <ohger1s@gmail.com>: Nov 28 08:01AM -0800

On Saturday, November 26, 2022 at 7:54:51 PM UTC-5, Beeper wrote:
 
 
> Thank you. Would you mind elaborating about the supposed worth of a 40"
> TV? Would a smaller or larger TV be more suitable for the room it is
> intended? I am sincerely curious.
 
Speaking from a repairer's standpoint, you need to price the job out the door for a max of 1/2 the replacement cost of the product. If the TV is yours, then your labor is free (something that it is NOT for a professional) and worth the repair if you 1) like the TV and 2) don't break the screen or damage the bonding in the process.
 
As for screen size, that is up to the end user.
rozwani kamsani <rozwanikamsani97@gmail.com>: Nov 27 10:13PM -0800

On Saturday, April 2, 2022 at 9:38:05 AM UTC+8, nathaniel peralta wrote:
 
> > ___________________________________________________________________________________________________
> Hello! can I ask for a copy of this one:
> Solution manual Principles of Environmental Engineering and Science (3rd Ed., Mackenzie Davis & Susan Masten)
Hi, Good day.
May I get the soft copy for Solution manual Introduction to Environmental Engineering (4th Ed., MacKenzie Davis & David Cornwell)?
Three Jeeps <jjhudak4@gmail.com>: Nov 27 10:13AM -0800

On Friday, November 25, 2022 at 8:46:31 AM UTC-5, Cursitor Doom wrote:
> >global with no timeout.
> Nothing to do with Agent. I'm trying to find the part I want on
> Mouser's website with Firefox or Opera - and failing badly.
You may want to try MS Edge, or its close cousin, Chrome.
j
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Digest for sci.electronics.repair@googlegroups.com - 9 updates in 2 topics

Cursitor Doom <cd@notformail.com>: Nov 25 11:09AM

I can't get any sense out of Mouser's website. You'd have thought
finding a diode would be simple enough; the spec ain't that hard to
meet: 600V 3A fast recovery diode with through-hole cylindrical
encapsulation. Can I find one on their site? Nope! Seems they don't
stock them any more.
The original part number was SR3523 but no data available on the net!
Anyone got any old diode data books to hand?
"Peter W." <peterwieck33@gmail.com>: Nov 25 04:02AM -0800

https://www.mouser.com/c/semiconductors/discrete-semiconductors/diodes-rectifiers/?if%20-%20forward%20current=3%20A&mounting%20style=Through%20Hole&vr%20-%20reverse%20voltage=600%20V
 
Got a whole sheet of them. Just use the filters.
 
Peter Wieck
Melrose Park, PA
Cursitor Doom <cd@notformail.com>: Nov 25 12:49PM

On Fri, 25 Nov 2022 04:02:47 -0800 (PST), "Peter W."
 
>Got a whole sheet of them. Just use the filters.
 
>Peter Wieck
>Melrose Park, PA
 
None of those are fast recovery types, though. And on my browser at
any rate, the filters keep clearing by themselves.
Stephen Wolstenholme <steve@easynn.com>: Nov 25 01:31PM

On Fri, 25 Nov 2022 12:49:58 +0000, Cursitor Doom <cd@notformail.com>
wrote:
 
>>Melrose Park, PA
 
>None of those are fast recovery types, though. And on my browser at
>any rate, the filters keep clearing by themselves.
 
That's strange for Agent. I think there is a setting to make filters
global with no timeout.
 
Steve
Cursitor Doom <cd@notformail.com>: Nov 25 01:46PM

On Fri, 25 Nov 2022 13:31:19 +0000, Stephen Wolstenholme
>>any rate, the filters keep clearing by themselves.
 
>That's strange for Agent. I think there is a setting to make filters
>global with no timeout.
 
Nothing to do with Agent. I'm trying to find the part I want on
Mouser's website with Firefox or Opera - and failing badly.
steve1001908@outlook.com: Nov 25 02:53PM

On Fri, 25 Nov 2022 13:46:26 +0000, Cursitor Doom <cd@notformail.com>
wrote:
 
>>global with no timeout.
 
>Nothing to do with Agent. I'm trying to find the part I want on
>Mouser's website with Firefox or Opera - and failing badly.
 
I just looked at your message headers and saw your Agent browser. I
should be more careful.
 
Steve
Paul Babiak <noway@uwish.com>: Nov 25 10:37AM -0500

On 11/25/2022 06:09 AM, Cursitor Doom wrote:
> stock them any more.
> The original part number was SR3523 but no data available on the net!
> Anyone got any old diode data books to hand?
 
UF5406
 
https://www.mouser.ca/ProductDetail/Diotec-Semiconductor/UF5406?qs=OlC7AqGiEDl14tlpPZuYug%3D%3D
Bob F <bobnospam@gmail.com>: Nov 24 05:50PM -0800

On 11/19/2022 10:40 PM, Bob F wrote:
> still have found no service manual for.
 
> The order was made 11/8, promised for Dec 2, and receive Nov 19. That
> surprised me.
 
I tried this replacement today. It would not load cd's, DVD's, or Blue
ray discs. Maybe needs adjustment, but I do not have much info on that
process. Since none of the disc types works, I don't have much hope for
that. I did not find any kind of jumper to remove. It looks just like
the origional.
 
I put the old one back in with the previous problem continues. I did
find that it hardly moves the disc at all on DVD's, but spins up CD's
and BluRay's quickly. Even blank CD's and DVD's do not change the
results. The DVD's still do not spin, the CD's spin and search for awhile.
 
How does the player detect the type of disc? It seems like for DVD's it
is very quickly giving up on spinning the disc.
 
I did find a youtube on a very similar disc player that includes what
looks like the same laser head unit. SOH-BDP5G
https://www.youtube.com/watch?v=9bXWrO9CLDs
 
From that, I learned the the VR1 is for BD, VR2 for DVD, and VR3 is CD.
 
I guess the next step is to get out the scope for adjustment.
"ohg...@gmail.com" <ohger1s@gmail.com>: Nov 25 06:50AM -0800

On Thursday, November 24, 2022 at 8:50:21 PM UTC-5, Bob F wrote:
> https://www.youtube.com/watch?v=9bXWrO9CLDs
 
> From that, I learned the the VR1 is for BD, VR2 for DVD, and VR3 is CD.
 
> I guess the next step is to get out the scope for adjustment.
 
 
I admit I'm confused by your original symptom of the machine not giving the DVD more than a brief sniff before bailing. My only guess is that it's not reading any reflection back with the DVD. Maybe DVDs are a bit less reflective than CDs?
 
As far as the "new" drive, I think it's very likely that the drive you received is junk probably pulled from a defective machine that arrived in one of the thousands of containers of scrap electronics that get shipped back to China every year.
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Digest for sci.electronics.repair@googlegroups.com - 19 updates in 2 topics

legg <legg@nospam.magma.ca>: Nov 23 10:55AM -0500

On Sun, 06 Nov 2022 10:07:50 -0800, Jeff Liebermann <jeffl@cruzio.com>
wrote:
 
>higher voltage rating. A few drive transistors burnt/shorted and
>replaced those."
 
>Maybe give Samlex a call and ask for a better schematic?
 
I've cut tracks to monitor power fet current in the offending
side of the bridge, and see noticeable crossconduction there
under all load conditions, when pwming.
 
The fet driver board, powered and running in isolation, shows
no gate drive issues - dead time is actually generated on this
board. ~500nS should be sufficient with 10R series gate
resistors, and there is no difficulty demonstrated in driving
capacitive loads.
 
A modest negative 'off' bias is developed by zener/dc restoration
on a series coupling capacitor.
 
It's basically just an isolated buffer with full fet control
deveoped in a separate small signal section.
 
The presence of cross-conduction makes no sense, if the gate
drive circuit is testing functional, though it would easily be
attributed as causal in early limiting of the phase arm.
 
RL
Chris Green <cl@isbd.net>: Nov 22 05:04PM


> > Birds manage with internal testes.
 
> I was always told our testes needed to be 36C, not 37C like inside us.
> Yet a bird is 40C body temperature.
 
Yes, but why do they need to be a bit cooler than our body
temperature? Wouldn't it make much more sense in evolutionary terms
for them to work properly at body temperature?
 
--
Chris Green
·
"Commander Kinsey" <CK1@nospam.com>: Nov 22 05:25PM


> Yes, but why do they need to be a bit cooler than our body
> temperature? Wouldn't it make much more sense in evolutionary terms
> for them to work properly at body temperature?
 
Indeed, as I said birds have them operating at 40C, so it's entirely possible for them to work at our 37C.
 
Maybe it's to attract the female. But in birds the need to not have them causing aerodynamic drag when flying is greater, besides they have pretty feathers to show off instead.
Peeler <trolltrap@valid.invalid>: Nov 22 06:36PM +0100

On Tue, 22 Nov 2022 17:04:26 +0000, Chris Green, the mentally deficient,
notorious, troll-feeding, senile idiot, blathered again:
 
 
> Yes, but why do they need to be a bit cooler than our body
> temperature? Wouldn't it make much more sense in evolutionary terms
> for them to work properly at body temperature?
 
Don't worry, senile sucker of troll cock. The unwashed wanker's cock will
quickly take on the temperature in your mouth!
Ed Pawlowski <esp@snet.xxx>: Nov 22 12:55PM -0500

On 11/22/2022 12:04 PM, Chris Green wrote:
 
> Yes, but why do they need to be a bit cooler than our body
> temperature? Wouldn't it make much more sense in evolutionary terms
> for them to work properly at body temperature?
 
It is in the works but evolution is slow. Probably will take another
30,000 years to eliminate the scrotum. OTOH, if you piss off you wife
it may be eliminated in one day.
Tim+ <tim.downie@gmail.com>: Nov 22 05:59PM


> Yes, but why do they need to be a bit cooler than our body
> temperature? Wouldn't it make much more sense in evolutionary terms
> for them to work properly at body temperature?
 
You're forgetting sexual selection. Women clearly selected men with ugly
dangly bits. ;-)
 
Tim
 
--
Please don't feed the trolls
"Commander Kinsey" <CK1@nospam.com>: Nov 22 06:00PM


> It is in the works but evolution is slow. Probably will take another
> 30,000 years to eliminate the scrotum. OTOH, if you piss off you wife
> it may be eliminated in one day.
 
Birds have already done it.
"Commander Kinsey" <CK1@nospam.com>: Nov 22 06:03PM

>> for them to work properly at body temperature?
 
> You're forgetting sexual selection. Women clearly selected men with ugly
> dangly bits. ;-)
 
Presumably they like them.
 
Mind you, not sure why so many short-cocked men still exist. The internet says the average is a pathetic 6 inches. If I had 6 inches, it would fall out whenever I drew back a bit.
"Peter W." <peterwieck33@gmail.com>: Nov 22 11:05AM -0800

> Mind you, not sure why so many short-cocked men still exist. The internet says the average is a pathetic 6 inches. If I had 6 inches, it would fall out whenever I drew back a bit.
 
I take back everything about blissful and invincible. Ignorance is curable.
 
You are, for the record, incurably stupid, and entirely unencumbered by the thought process.
 
Peter Wieck
Melrose Park, PA
"Rod Speed" <rod.speed.aaa@gmail.com>: Nov 23 06:47AM +1100

On Tue, 22 Nov 2022 22:49:53 +1100, Max Demian <max_demian@bigfoot.com>
wrote:
 
>> And atheists would consider it correctly evolved for purpose, so why
>> alter it?
 
> Why doesn't it retract when not in use, like dogs?
 
You can run the same line about fur, why don't
humans have fur like apes and dogs and cats ?
 
> And why oh why are mammalian testicles outside the body?
 
There is some line about that allowing the testicies to be cooler.
 
> Birds manage with internal testes.
 
Not sure if birds have the same body temperatures.
 
Maybe hanging out in the breeze wouldnt work as well with flying animals
like birds, they could get caught on branches etc when landing on a branch.
Peeler <trolltrap@valid.invalid>: Nov 22 09:24PM +0100

On Wed, 23 Nov 2022 06:47:25 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:
 
<FLUSH the abnormal trolling senile cretin's latest trollshit unread>
 
--
The Natural Philosopher about senile Rodent:
"Rod speed is not a Brexiteer. He is an Australian troll and arsehole."
Message-ID: <pu07vj$s5$2@dont-email.me>
farter <tsruhf@gmail.com>: Nov 23 07:54AM +1100


> Yes, but why do they need to be a bit cooler than our body
> temperature? Wouldn't it make much more sense in evolutionary terms
> for them to work properly at body temperature?
 
Maybe that is easier said than done with the higher mammals.
 
There has to be a reason that it is so common.
Peeler <trolltrap@valid.invalid>: Nov 22 09:57PM +0100

On Wed, 23 Nov 2022 07:54:06 +1100, farter, better known as cantankerous
trolling senile geezer Rodent Speed, wrote:
 
<FLUSH the abnormal trolling senile cretin's latest trollshit unread>
 
--
Website (from 2007) dedicated to the 88-year-old senile Australian
cretin's pathological trolling:
https://www.pcreview.co.uk/threads/rod-speed-faq.2973853/
farter <tsruhf@gmail.com>: Nov 23 08:07AM +1100

>> for them to work properly at body temperature?
 
> It is in the works but evolution is slow. Probably will take another
> 30,000 years to eliminate the scrotum.
 
The problem with that line is that the higher mammals like
humans and even cattle and sheep evolved after birds.
farter <tsruhf@gmail.com>: Nov 23 08:09AM +1100

>> for them to work properly at body temperature?
 
> You're forgetting sexual selection. Women clearly selected men with ugly
> dangly bits. ;-)
 
Doesn't explain cattle, dogs and sheep.
Bob F <bobnospam@gmail.com>: Nov 22 01:38PM -0800

On 11/22/2022 9:04 AM, Chris Green wrote:
 
> Yes, but why do they need to be a bit cooler than our body
> temperature? Wouldn't it make much more sense in evolutionary terms
> for them to work properly at body temperature?
 
Better get the GOP working to pass legislation to make it the way you
want it.
"Commander Kinsey" <CK1@nospam.com>: Nov 22 10:10PM

>> for them to work properly at body temperature?
 
> Better get the GOP working to pass legislation to make it the way you
> want it.
 
Somebody has to fix things, the liberal thieves certainly won't.
 
By the way, Gauntlet Of Power?
Peeler <trolltrap@valid.invalid>: Nov 22 11:10PM +0100

On Wed, 23 Nov 2022 08:07:04 +1100, farter, better known as cantankerous
trolling senile geezer Rodent Speed, wrote:
 
<FLUSH the abnormal trolling senile cretin's latest trollshit unread>
 
--
Norman Wells addressing trolling senile Rodent:
"Ah, the voice of scum speaks."
MID: <g4t0jtFrknaU1@mid.individual.net>
Peeler <trolltrap@valid.invalid>: Nov 22 11:11PM +0100

On Wed, 23 Nov 2022 08:09:00 +1100, farter, better known as cantankerous
trolling senile geezer Rodent Speed, wrote:
 
<FLUSH the abnormal trolling senile cretin's latest trollshit unread>
 
--
Bod addressing abnormal senile quarreller Rodent Speed:
"Do you practice arguing with yourself in an empty room?"
MID: <g4ihlaFh5p5U2@mid.individual.net>
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Digest for sci.electronics.repair@googlegroups.com - 7 updates in 3 topics

"Commander Kinsey" <CK1@nospam.com>: Nov 21 06:56PM


> No - also Muslims, and also common in many parts of the world (although
> it's mainly the Jews who make a big religious thing of it).
> https://en.wikipedia.org/wiki/Circumcision
 
You'd think religious folk would consider the penis designed correctly by god, so why alter it?
 
And atheists would consider it correctly evolved for purpose, so why alter it?
"Peter W." <peterwieck33@gmail.com>: Nov 21 11:09AM -0800

Just like the appendix!
 
So, a thought did cross your mind. Must have been a long and lonely journey!
 
Both blissful and invincible!
 
Peter Wieck
Melrose Park, PA
Max Demian <max_demian@bigfoot.com>: Nov 22 11:49AM

On 21/11/2022 18:56, Commander Kinsey wrote:
> by god, so why alter it?
 
> And atheists would consider it correctly evolved for purpose, so why
> alter it?
 
Why doesn't it retract when not in use, like dogs? And why oh why are
mammalian testicles outside the body? Birds manage with internal testes.
 
--
Max Demian
"Commander Kinsey" <CK1@nospam.com>: Nov 22 12:25PM


>> And atheists would consider it correctly evolved for purpose, so why
>> alter it?
 
> Why doesn't it retract when not in use, like dogs?
 
1) It feels good to have it flap about - every gone naked hillwalking or running or swimming?
2) It's a show-off piece.
 
> And why oh why are
> mammalian testicles outside the body?
 
Yeah that's daft. Ever sat on your own balls when it's too warm? That hurts.
 
To be fair unless it's a really warm day, they semi retract. Go ice swimming and they're almost inside.
 
> Birds manage with internal testes.
 
I was always told our testes needed to be 36C, not 37C like inside us. Yet a bird is 40C body temperature.
Peeler <trolltrap@valid.invalid>: Nov 22 04:14PM +0100

On Tue, 22 Nov 2022 11:49:53 +0000, Max Dumb, the REAL dumb, notorious,
troll-feeding senile idiot, blathered again:
 
 
> Why doesn't it retract when not in use, like dogs? And why oh why are
> mammalian testicles outside the body? Birds manage with internal testes.
 
Oh, and why oh why are both of you bullshitting retarded trolling shitheads?
bruce bowser <bruce2bowser@gmail.com>: Nov 21 11:34AM -0800

On Sunday, November 13, 2022 at 11:01:10 PM UTC-5, legg wrote:
> >S
 
> It may need a battery inserted, to start with a charger
> inserted.
 
It looks like there are several watch-sized batteries. Its in many of these foreign-builts.
Bob F <bobnospam@gmail.com>: Nov 21 09:24AM -0800


>> The order was made 11/8, promised for Dec 2, and receive Nov 19. That
>> surprised me.
 
> It's been *many* years since I played with DVD players (when they became uneconomical to repair), but I recall many lasers being shipped with a solder blob jumper on the ribbon cable to prevent static damage. The blob had to be removed after the laser was installed. If the laser doesn't work at all, see if there's a blob jumper on the ribbon. There also might be a trimmer adjustment on the kapton ribbon, but I wouldn't try adjusting that until every option is exhausted. I recall tweaking that a bit as the laser got older to improve readability, but pushing it too high would also damage the laser diode IIRC.
 
Excellent advise. The rains are coming, so I will have more indoor time
to spend on this project.
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Digest for sci.electronics.repair@googlegroups.com - 1 update in 1 topic

"ohg...@gmail.com" <ohger1s@gmail.com>: Nov 21 07:01AM -0800

On Sunday, November 20, 2022 at 1:40:29 AM UTC-5, Bob F wrote:
> still have found no service manual for.
 
> The order was made 11/8, promised for Dec 2, and receive Nov 19. That
> surprised me.
 
It's been *many* years since I played with DVD players (when they became uneconomical to repair), but I recall many lasers being shipped with a solder blob jumper on the ribbon cable to prevent static damage. The blob had to be removed after the laser was installed. If the laser doesn't work at all, see if there's a blob jumper on the ribbon. There also might be a trimmer adjustment on the kapton ribbon, but I wouldn't try adjusting that until every option is exhausted. I recall tweaking that a bit as the laser got older to improve readability, but pushing it too high would also damage the laser diode IIRC.
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Digest for sci.electronics.repair@googlegroups.com - 1 update in 1 topic

Bob F <bobnospam@gmail.com>: Nov 19 10:40PM -0800

On 11/7/2022 12:47 PM, Bob F wrote:
 
> I tried holding "PLAY" or "PAUSE" for 8 seconds to reset to factory
> settings with no effect. (Does nothing)
 
> Any ideas about getting it working would be appreciated.
 
 
Update:
 
I just received a replacement laser unit from Alibaba in China for $15.
Hopefully, I can just remove the old one and replace it and it will
work. Or will the replacement still need calibration adjustments that I
still have found no service manual for.
 
The order was made 11/8, promised for Dec 2, and receive Nov 19. That
surprised me.
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