sci.electronics.repair@googlegroups.com

Today's topics:

* Two phases or not? - 5 messages, 3 authors
http://groups.google.com/group/sci.electronics.repair/t/0a29a801d6e01e9e?hl=en
* Laptop not charging. - 3 messages, 3 authors
http://groups.google.com/group/sci.electronics.repair/t/3f52116e8141f1a4?hl=en
* If you are going to blow a motor, blow it out of the vehicle! - 2 messages,
2 authors
http://groups.google.com/group/sci.electronics.repair/t/66e4c30ba9ca1e0c?hl=en
* DTV sound synch - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/2896d12048fef530?hl=en
* CRT Monitor Philips black screen when cold - 5 messages, 3 authors
http://groups.google.com/group/sci.electronics.repair/t/5e3cab73ac7d259c?hl=en
* possibly OT: players reject region 0 DVD - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/b38242427b60f545?hl=en
* Yamaha EMX5016 mixer amp from 2006 - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/bc288deddd9278ea?hl=en

==============================================================================
TOPIC: Two phases or not?
http://groups.google.com/group/sci.electronics.repair/t/0a29a801d6e01e9e?hl=en
==============================================================================

== 1 of 5 ==
Date: Sat, Jan 29 2011 5:35 pm
From: "Phil Allison"

"Mark Cross"
>
> To understand what is "magical" about that you will need to know phasors
> and
> the math related to that. Once you understand the math that support
> phasors,
> you clearly see why 0º and 180º are the same phasor.

** ABSOLUTE Bollocks.

> http://en.wikipedia.org/wiki/Phasor

** Says nothing of the kind whatever.

( Bet the only "phasors" this jerk knows about are the ones used on "Star
Trek")

Fuck of you pathetic, bloody TROLL 1!

..... Phil

== 2 of 5 ==
Date: Sat, Jan 29 2011 6:38 pm
From: David Nebenzahl

On 1/29/2011 5:35 PM Phil Allison spake thus:

>"Mark Cross"
>>
>> To understand what is "magical" about that you will need to know
>> phasors and the math related to that. Once you understand the math
>> that support phasors, you clearly see why 0� and 180� are the same
>> phasor.
>
> ** ABSOLUTE Bollocks.
>
>> http://en.wikipedia.org/wiki/Phasor
>
> ** Says nothing of the kind whatever.
>
> ( Bet the only "phasors" this jerk knows about are the ones used on "Star
> Trek")
>
> Fuck of you pathetic, bloody TROLL 1!

Phil, I happen to agree with you here, so do you think you could try to
restrain yourself a little bit and not go off the deep end? Tends to
ruin whatever good points you make ...

--
Comment on quaint Usenet customs, from Usenet:

To me, the *plonk...* reminds me of the old man at the public hearing
who stands to make his point, then removes his hearing aid as a sign
that he is not going to hear any rebuttals.

== 3 of 5 ==
Date: Sat, Jan 29 2011 7:01 pm
From: Jamie

David Nebenzahl wrote:

> On 1/29/2011 5:35 PM Phil Allison spake thus:
>
>> "Mark Cross"
>>
>>>
>>> To understand what is "magical" about that you will need to know
>>> phasors and the math related to that. Once you understand the math
>>> that support phasors, you clearly see why 0º and 180º are the same
>>> phasor.
>>
>>
>> ** ABSOLUTE Bollocks.
>>
>>> http://en.wikipedia.org/wiki/Phasor
>>
>>
>> ** Says nothing of the kind whatever.
>>
>> ( Bet the only "phasors" this jerk knows about are the ones used on
>> "Star Trek")
>>
>> Fuck of you pathetic, bloody TROLL 1!
>
>
> Phil, I happen to agree with you here, so do you think you could try to
> restrain yourself a little bit and not go off the deep end? Tends to
> ruin whatever good points you make ...
>
>
Yes, Phil is correct in his insertion how ever, you can't teach a lot
to fuse pullers, I don't know why Phil even tries.

Jamie

== 4 of 5 ==
Date: Sat, Jan 29 2011 6:51 pm
From: "Phil Allison"

"David Nebenzahl"
>>"Mark Cross"
>>>
>>> To understand what is "magical" about that you will need to know phasors
>>> and the math related to that. Once you understand the math
>>> that support phasors, you clearly see why 0� and 180� are the same
>>> phasor.
>>
>> ** ABSOLUTE Bollocks.
>>
>>> http://en.wikipedia.org/wiki/Phasor
>>
>> ** Says nothing of the kind whatever.
>>
>> ( Bet the only "phasors" this jerk knows about are the ones used on "Star
>> Trek")
>>
>> Fuck of you pathetic, bloody TROLL !!
>
> Phil, I happen to agree with you here, so do you think you could try to
> restrain yourself a little bit and not go off the deep end? Tends to ruin
> whatever good points you make ...

** Cross has been posting this same sort of brain dead drivel here for
ears - he is totally off with the fairies and beyond all help. There is no
reason whatever to tolerate such vexatious persons.

I see it as a great folly for anyone to do that.

PS:

Usenet is not the real world - usenet is an on-line jungle.

In normal life, I am usually a polite and cheerful person.

..... Phil

== 5 of 5 ==
Date: Sat, Jan 29 2011 7:09 pm
From: "Phil Allison"

"David Nebenzahl"
>
> Actually, there is at least one application which depends on there being 2
> phases in ordinary residential power distribution panels: the so-called
> Edison circuit. This is where two circuits are run with separate "hots"
> and a common neutral, where the neutral conductor is the same size as the
> hots.
>
> The only way this can work is if the two circuits are separate phases (in
> this case, 180� apart), so that the currents cancel in the common return
> conductor.
>
> Apart from this, we wouldn't care if the two legs of the power company's
> step-down transformer delivered the same phase of power (just give us the
> juice! who cares about the phase?).

** Remember the BBC 1960s TV show:

" Never mind the quality - feel the width "

.... Phil

==============================================================================
TOPIC: Laptop not charging.
http://groups.google.com/group/sci.electronics.repair/t/3f52116e8141f1a4?hl=en
==============================================================================

== 1 of 3 ==
Date: Sat, Jan 29 2011 6:12 pm
From: T i m

On Sat, 29 Jan 2011 08:04:05 -0600, Ken <Ken@invalid.com> wrote:

> I see you have a reply that directs you to a website for a schematic.
>That might be useful.

If I could get to that it could be handy because ..

> But not having worked on your computer or one
>like it before, here is what I would do:
>
> If the trouble began when the PS lead was pulled, it is possible that
>too high a voltage might have been applied if there is a feedback lead
>for the PS and it was broken. That might have applied too great a
>voltage to the laptop. This is just theory you understand.

Understood ...
>
> I would plug in a known good PS and with a DVM measure both ends of
>components near the connector. Look especially close for low value
>resistors or anything that might be a SM fuse.

Thinking about that and what has been said later that makes a lot of
sense and there /is/ a sm device of some sort right behind that socket
(sm stuff was only just being used as I was leaving the trade) so that
could well be it. I guess it's either a sm fuse or diode and it
shouldn't be difficult to test for either.

The lad has just found this site / pictures. ;-)

http://www.deliran.net/refrence/Inspiron_1545/images/tear/SystemboardFirst.jpg

This last pictures here show the charging board pretty clearly (top
left corner is the DC socket).

http://www.deliran.net/refrence/Inspiron_1545/Inspiron_1545_eng/td_fan.htm

You can just see the charger board under the system board top left.
Luckily it looks like you can get to the back of the socket and
'device' with the thing mostly in one piece. Soo, if I measure a
voltage on one side of said device and not the other (with battery in
and charger in an on) /and/ it looks like it's wired in series with
the power socket it would most likely be a fuse?

> If too great a voltage
>were applied you might have opened a component and that is why a good PS
>still does not work.

Yup, nor charge what could be a good (second) battery.

> Also look at the daughter board if it is attached
>with a connector to the mother board. A tug on the power connector
>might have caused a poor connection where the daughter board meets the MB.

It is connected by hard mounted plug / socket pair and I checked for
any possible movement damage on there but the board sits on shouldered
mounting pillars and is still a very rigid connection.

We didn't try to power it up with just the chassis as you have to take
the cpu heatsink off to get the system board off the top of said
charging board but looking back at it with a voltage measurement in
mind it might nearly be doable with just the rear top cover removed
(two screws). I'll have a look in the morning. ;-)

Assuming it is a fuse, are they normally marked with their rating and
if so and if there is space, could I tack a suitably rated / type wire
ended fuse / fusewire in place as an experiment at least?

Looking at eBay if it is the board then 30 quid isn't too terrible
(compared with a new laptop especially).

A fuse would be cheaper of course. ;-)

Cheers, T i m

== 2 of 3 ==
Date: Sat, Jan 29 2011 6:44 pm
From: Ken

T i m wrote:
> On Sat, 29 Jan 2011 08:04:05 -0600, Ken<Ken@invalid.com> wrote:
>
>> I see you have a reply that directs you to a website for a schematic.
>> That might be useful.
>
> If I could get to that it could be handy because ..
>
>> But not having worked on your computer or one
>> like it before, here is what I would do:
>>
>> If the trouble began when the PS lead was pulled, it is possible that
>> too high a voltage might have been applied if there is a feedback lead
>> for the PS and it was broken. That might have applied too great a
>> voltage to the laptop. This is just theory you understand.
>
> Understood ...
>>
>> I would plug in a known good PS and with a DVM measure both ends of
>> components near the connector. Look especially close for low value
>> resistors or anything that might be a SM fuse.
>
> Thinking about that and what has been said later that makes a lot of
> sense and there /is/ a sm device of some sort right behind that socket
> (sm stuff was only just being used as I was leaving the trade) so that
> could well be it. I guess it's either a sm fuse or diode and it
> shouldn't be difficult to test for either.
>
> The lad has just found this site / pictures. ;-)
>
> http://www.deliran.net/refrence/Inspiron_1545/images/tear/SystemboardFirst.jpg
>
> This last pictures here show the charging board pretty clearly (top
> left corner is the DC socket).
>
> http://www.deliran.net/refrence/Inspiron_1545/Inspiron_1545_eng/td_fan.htm
>
> You can just see the charger board under the system board top left.
> Luckily it looks like you can get to the back of the socket and
> 'device' with the thing mostly in one piece. Soo, if I measure a
> voltage on one side of said device and not the other (with battery in
> and charger in an on) /and/ it looks like it's wired in series with
> the power socket it would most likely be a fuse?

Is there any component designation?? Such as "F1" stamped on the
board? Sometimes such a designation can tell you what the component is.
Is there any marking on the component? That also could tell you what
it is. Are there any similar components elsewhere on the board? What
is the resistance across other components of the same type compared to
this one?

>
>> If too great a voltage
>> were applied you might have opened a component and that is why a good PS
>> still does not work.
>
> Yup, nor charge what could be a good (second) battery.
>
>> Also look at the daughter board if it is attached
>> with a connector to the mother board. A tug on the power connector
>> might have caused a poor connection where the daughter board meets the MB.
>
> It is connected by hard mounted plug / socket pair and I checked for
> any possible movement damage on there but the board sits on shouldered
> mounting pillars and is still a very rigid connection.
>
> We didn't try to power it up with just the chassis as you have to take
> the cpu heatsink off to get the system board off the top of said
> charging board but looking back at it with a voltage measurement in
> mind it might nearly be doable with just the rear top cover removed
> (two screws). I'll have a look in the morning. ;-)
>
> Assuming it is a fuse, are they normally marked with their rating and
> if so and if there is space, could I tack a suitably rated / type wire
> ended fuse / fusewire in place as an experiment at least?
>
> Looking at eBay if it is the board then 30 quid isn't too terrible
> (compared with a new laptop especially).
>
> A fuse would be cheaper of course. ;-)
>
> Cheers, T i m

== 3 of 3 ==
Date: Sat, Jan 29 2011 10:22 pm
From: Fred

T i m <news@spaced.me.uk> wrote in
news:3jv7k654r4j25nunqb0dgnfsurhqkev45i@4ax.com:

> Cheers, T i m
>

Get a competent technician to take the laptop apart and resolder all the
connections between the power jack and the circuit board it is SUPPOSED
to be soldered to. They get a hairline crack in the solder because
that's the only thing holding the connector to the board. These cracks
can be so thin you need a jeweler's loupe to see them, if you find them
at all.

Resoldering the connector to the board fixes the problem.

The competent technician will, of course, load test her AC power supply
before tearing into the computer, bending and pulling hard on the plug at
the computer end to make sure the wires inside the plug and cable have
not been broken, another common source of intermittent power, but you did
say it was powering the computer so that's probably not the problem.
There is a switch telling the computer the power supply is plugged in on
many models moved by the power supply plug and that switch's connections
may be intermittent.

==============================================================================
TOPIC: If you are going to blow a motor, blow it out of the vehicle!
http://groups.google.com/group/sci.electronics.repair/t/66e4c30ba9ca1e0c?hl=en
==============================================================================

== 1 of 2 ==
Date: Sat, Jan 29 2011 6:37 pm
From: RoadRunner

If you're going to blow a motor you might as well blow it sky high!

http://www.craigboyce.com/w/2011/01/awesome-blown-motor/

== 2 of 2 ==
Date: Sat, Jan 29 2011 10:39 pm
From: Fred

RoadRunner <asdf@aol.com> wrote in news:vfj9k6lrkvtvfce829s09m5grtc6913un1@
4ax.com:

> http://www.craigboyce.com/w/2011/01/awesome-blown-motor/

Awesome!

==============================================================================
TOPIC: DTV sound synch
http://groups.google.com/group/sci.electronics.repair/t/2896d12048fef530?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 29 2011 9:05 pm
From: stratus46@yahoo.com

On Jan 29, 4:29 pm, "Dave Plowman (News)" <d...@davenoise.co.uk>
wrote:
> In article
> <d7b4be9b-6843-425c-92c4-62788a327...@f30g2000yqa.googlegroups.com>,
>    <stratu...@yahoo.com> wrote:
>
> > It still does mean something and if you ever thought revenue WASN'T a
> > part of it, you're just wrong. I get to see 'broadcast quality' video
> > from the 60's and 70's at work and while it was good in its day, it
> > doesn't hold a candle to what you have now. I'm one of those 'techs'
> > and I can tell you we DO give a hoot about how it looks and sounds.
>
> It's very unlikely you are seeing broadcast electronic video from
the 60s
> and 70s as good as it was then. It'll have been transferred a few
times as
> tape formats go out of use - and the transfer equipment likely
towards the
> end of its life. Plus the fact that even a single generation of
quad VTR
> caused noticeable degradation, and most of the stuff which has been
kept
> will be two or more generations.
>
> --
> *If you try to fail and succeed, which have you done? *
>
>     Dave Plowman        d...@davenoise.co.uk           London SW
>                   To e-mail, change noise into sound.

It IS unlikely but I work in Hollywood and am one of the few who still
get (got?) to work on quads so it happens to be true. I was watching
the original 2" quad tape played back on an Ampex AVR-1 just a few
weeks ago. It was an NBC Danny Thomas special (low band color so there
was some moire) from 1965 with Johnny Carson, Bill Cosby, Tim Conway
and others You're also mistaken about how many generations you can go
down before you have noticeable problems. Network on air tapes were a
minimum of 3 generations down. Mind you, it's necessary to adjust
things properly unlike the newest digital machines that are close to
idiot proof but will tie you in knots with the myriad settings.

You probably never saw a Super High Band Pilot quad tape where the
time base reference was recorded analog along with the analog FM
video. Zero velocity errors as the pilot was the sample clock and any
timing errors on the video were also in the pilot so the error was
nada. That came out in the '70s along with the first 1 inch decks
which had the 'trick' video of slo-mo and still frames which were
previously unavailable to local stations. Quad died fast after that
but not until having a 20+ year run.

I was just repairing Ampex AVR-3s this afternoon.
G²

==============================================================================
TOPIC: CRT Monitor Philips black screen when cold
http://groups.google.com/group/sci.electronics.repair/t/5e3cab73ac7d259c?hl=en
==============================================================================

== 1 of 5 ==
Date: Sat, Jan 29 2011 10:26 pm
From: Fred

"Steinway" <slkjdskd> wrote in
news:4d4439d7$0$2045$4fafbaef@reader1.news.tin.it:

> Hallo!
> My CRT monitor, Philips 109B, has black screen after 2 seconds when it
> is cold: the picture becomes bigger and fades away.
> If I turn it off and turn on, the picture again becomes bigger and
> fades out.
> When it is warm, after 20-30 minutes, if I turn it off and turn on,
> the screen appears and works very good.
> Could it be a cap?
> Thank you!
> S.
>
>
>

Junk it! It's time to upgrade to a flatscreen.

A new flatscreen twice as big as the CRT and a hundred kilos lighter
costs half as much as fixing the old CRT.

== 2 of 5 ==
Date: Sun, Jan 30 2011 12:13 am
From: Sylvia Else

On 30/01/2011 5:26 PM, Fred wrote:
> "Steinway"<slkjdskd> wrote in
> news:4d4439d7$0$2045$4fafbaef@reader1.news.tin.it:
>
>> Hallo!
>> My CRT monitor, Philips 109B, has black screen after 2 seconds when it
>> is cold: the picture becomes bigger and fades away.
>> If I turn it off and turn on, the picture again becomes bigger and
>> fades out.
>> When it is warm, after 20-30 minutes, if I turn it off and turn on,
>> the screen appears and works very good.
>> Could it be a cap?
>> Thank you!
>> S.
>>
>>
>>
>
> Junk it! It's time to upgrade to a flatscreen.
>
> A new flatscreen twice as big as the CRT and a hundred kilos lighter
> costs half as much as fixing the old CRT.
>

Depends how much it costs to fix the CRT. If it's a bad cap, it might be
obvious which one just by looking at it (bulging top and/or leaking),
and the fix, excluding the OP's time, may cost a few dollars.

The OP should of course make sure he's aware of the hazards associated
with CRTs even when there's no power applied.

Sylvia.

== 3 of 5 ==
Date: Sun, Jan 30 2011 12:20 am
From: "Steinway"

"Sylvia Else" <sylvia@not.here.invalid> ha scritto nel messaggio
news:8qkkteFd62U1@mid.individual.net...

> Depends how much it costs to fix the CRT. If it's a bad cap, it might be
> obvious which one just by looking at it (bulging top and/or leaking), and
> the fix, excluding the OP's time, may cost a few dollars.
>
> The OP should of course make sure he's aware of the hazards associated
> with CRTs even when there's no power applied.
>
> Sylvia.

In fact I'd like to repair it myself, without OP's time - if I can't repair
it, I buy another monitor :)

== 4 of 5 ==
Date: Sun, Jan 30 2011 12:27 am
From: "Steinway"

"circuit" <circuit@123456.tv> ha scritto nel messaggio
news:ii2ce4$d6h$1@speranza.aioe.org...
> bad cap in the flyback xfmr
>
>

Thank you!

== 5 of 5 ==
Date: Sun, Jan 30 2011 12:31 am
From: Sylvia Else

On 30/01/2011 7:20 PM, Steinway wrote:
> "Sylvia Else"<sylvia@not.here.invalid> ha scritto nel messaggio
> news:8qkkteFd62U1@mid.individual.net...
>
>> Depends how much it costs to fix the CRT. If it's a bad cap, it might be
>> obvious which one just by looking at it (bulging top and/or leaking), and
>> the fix, excluding the OP's time, may cost a few dollars.
>>
>> The OP should of course make sure he's aware of the hazards associated
>> with CRTs even when there's no power applied.
>>
>> Sylvia.
>
> In fact I'd like to repair it myself, without OP's time - if I can't repair
> it, I buy another monitor :)
>

I'm confused, or perhaps just befuzzled. Aren't you the OP (original
poster)?

Sylvia.

==============================================================================
TOPIC: possibly OT: players reject region 0 DVD
http://groups.google.com/group/sci.electronics.repair/t/b38242427b60f545?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 29 2011 10:37 pm
From: Fred

"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in
news:ii22t2$1vk$2@news.eternal-september.org:

>> Maybe the disc isn't detected as 0. Stick it in a PC DVD
>> player and use DVD Identifier to see what region info the
>> disc actually gives.
>
> Thank you! I didn't know how to do that.
>
> ---------------
>
> I still don't.
>
> I inserted the disk, and it auto-ran without prompting for a region,
> suggesting that the region was zero (that is, no specified region). I
> couldn't find anything in the Roxio applet to identify the region.
>
> Runs fine on a 10-year-old computer, by the way.
>
>
>> Did the BD or DVD player give you a more-specific error?
>
> The standalone DVD player which said specifically that the region was
> unacceptable.
>
>
>> Most allow a change of region up to 4 times.
>
> My Plextor PX-708A was bought primarily to burn CDs. I've never played
> a DVD in it, so I've never had to select a region. (I think it allows
> three changes.)
>
> By the way, Sony has already responded, and as you might guess, the
> answer had nothing whatever to do with the question.
>
>
>

Now that you have the computer playing movies is a great time to dump all
the DVD nonsense, learn how to download, decode and assemble the
thousands and thousands of movies posted to alt.binaries.movies.divx,
right here on usenet, every day. Does the big TV have a 3-row
"computer" input to plug the old computer into?

None of the DivX/XviD movies on alt.binaries.movies.divx have
restrictions on them, except when some jerk posts passworded RAR file
sets. Every movie of the 2010 Academy Awards and LOTS of them that
should have been nominated are posted to that newsgroup, continuously.

You're gonna need more Terabytes....(c;]

BTW, the finest movie of 2010, "Majesty" from the Netherlands is posted
there, in Dutch with hard-coded English subtitles. I think it beats "The
King's Speech" by miles. If your interested in learning how, it's easy
with a few low cost or free programs for any Windows box.

I bet I can't rent Majesty, in English or Dutch or Urdu in
America....pity.

Did I mention you're gonna need more Terabytes?

==============================================================================
TOPIC: Yamaha EMX5016 mixer amp from 2006
http://groups.google.com/group/sci.electronics.repair/t/bc288deddd9278ea?hl=en
==============================================================================

== 1 of 1 ==
Date: Sun, Jan 30 2011 1:00 am
From: "N_Cook"

N_Cook <diverse@tcp.co.uk> wrote in message
news:ii1n90$ii1$1@news.eternal-september.org...
> repair m on e-S and there is an inverter stuck in before the R ch o/p, not
> for the L
>
>
>
>

Is it just for evening up the ps?. If a momentary high draw from one PA on
+/ve rail dropping reservoir by 1V then also a matching 1V drop on the -ve
rail from the other ch, wheras usually that would be a 2V drop on + rail
only

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