sci.electronics.repair@googlegroups.com

Today's topics:

* Test Li Ion Batteries? - 5 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/7f8288ba4f888f5c?hl=en
* PAT testing damage (UK) - 18 messages, 7 authors
http://groups.google.com/group/sci.electronics.repair/t/eec67008cac87457?hl=en
* Connect TV audio output to old stereo amp - 2 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/f9517efe346c55f4?hl=en
* Sony TV - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/b4ecbdbddd551e09?hl=en

==============================================================================
TOPIC: Test Li Ion Batteries?
http://groups.google.com/group/sci.electronics.repair/t/7f8288ba4f888f5c?hl=en
==============================================================================

== 1 of 5 ==
Date: Wed, Jul 27 2011 9:06 am
From: Jeff Liebermann

On Wed, 27 Jul 2011 08:31:03 -0700 (PDT), KenO <kenitholson@yahoo.com>
wrote:

>The Li Ion battery pack I am most interested in checking is a Toshiba
>PA2490U (10.8V 3600mAh) While it is new to me the Laptop and battery
>pack is ~ 15 yrs old.

I have a few of those in the office. After 15 years, most are dead or
fairly close to dead. Any of the battery analyzer programs mentioned
should give you an estimated capacity. However, the best test is to
simply run the laptop on battery and see how long it lasts. If it
won't run the laptop, consider it dead.

>The only packs I have found are recycled ones

Check eBay:
<http://shop.ebay.com/i.html?_from=R40&_trksid=p5197.m570.l1313&_nkw=PA2490U>
Some used battery packs, probably in the same condition as yours.

>Some of the links you provided mention testing each cell of the pack.
>The Toshiba has 8 connectors between the - & + and 2 more so hope
>everything can be checked without opening the pack.

Those are sensors, protection circuitry, and i/o for the charge
controller in the battery back.

>Has anyone had experience with these Toshiba Li Ion packs?
>Ken

Only in replacing them.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

== 2 of 5 ==
Date: Thurs, Jul 28 2011 7:24 am
From: KenO

Hi Jeff,

"I have a few of those in the office.  After 15 years, most are dead
or fairly close to dead."

Have you opened any of your dead packs? If yes, any tips?

Am wondering if a cyanoacrylate was the adhesive? Have you tried a
debonder before opening packs?
http://solutions.3m.com/wps/portal/3M/en_US/electronics/home/productsandservices/products/ProductNavigator/TapeAdhesives/?PC_7_RJH9U5230GE3E02LECIE20KHO6_nid=56VVV1Y0SJbeB4XBZ0P1DBgl
 

Thanks again for all your help!

Ken

== 3 of 5 ==
Date: Thurs, Jul 28 2011 7:46 am
From: KenO

Hi Jeff,

"If you just want to test the battery itself, I use: <http://
www.westmountainradio.com/content.php?page=CBA> which produces nifty
graphs instead of a single number."

Since you have a number of these old Toshiba Li Ion packs, have you
run CBA tests on any or all the working ones?
http://www.westmountainradio.com/product_info.php?products_id=cba_software

Ken

== 4 of 5 ==
Date: Thurs, Jul 28 2011 9:49 am
From: Jeff Liebermann

On Thu, 28 Jul 2011 07:24:20 -0700 (PDT), KenO <kenitholson@yahoo.com>
wrote:

>"I have a few of those in the office.  After 15 years, most are dead
>or fairly close to dead."
>
>Have you opened any of your dead packs? If yes, any tips?

Nope. I haven't opened them. I keep a few on hand because some of
the early Toshiblah laptops would not run on charger power unless a
battery (dead or otherwise) was installed. I'll look at it to see how
it comes apart, but I don't want to wreck them.

>Am wondering if a cyanoacrylate was the adhesive? Have you tried a
>debonder before opening packs?
>http://solutions.3m.com/wps/portal/3M/en_US/electronics/home/productsandservices/products/ProductNavigator/TapeAdhesives/?PC_7_RJH9U5230GE3E02LECIE20KHO6_nid=56VVV1Y0SJbeB4XBZ0P1DBgl

Dunno. If it was cyanoacrylate, it will be brittle. Beat on the seam
with a stiff putty knife and you'll crack the glue joint. That works
on some other battery packs I've broken open.

Light reading on killing batteries:
<http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries>

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

== 5 of 5 ==
Date: Thurs, Jul 28 2011 9:52 am
From: Jeff Liebermann

On Thu, 28 Jul 2011 07:46:21 -0700 (PDT), KenO <kenitholson@yahoo.com>
wrote:

>"If you just want to test the battery itself, I use: <http://
>www.westmountainradio.com/content.php?page=CBA> which produces nifty
>graphs instead of a single number."
>
>Since you have a number of these old Toshiba Li Ion packs, have you
>run CBA tests on any or all the working ones?
>http://www.westmountainradio.com/product_info.php?products_id=cba_software

Nope. I'm mostly interested in unpackaged Li-Ion and LIPO unpackaged
batteries for model airplane and robotic use. Also, I've tested some
cell phone batteries and tested for some oddities, such as NiMH
batteries that actually increase in capacity on initial charge. It
takes a long time to test a battery properly, so I don't do it often.
The bigger the battery, the longer it takes to discharge.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

==============================================================================
TOPIC: PAT testing damage (UK)
http://groups.google.com/group/sci.electronics.repair/t/eec67008cac87457?hl=en
==============================================================================

== 1 of 18 ==
Date: Wed, Jul 27 2011 10:36 am
From: "Gareth Magennis"

Hi,

I have a Roland drum machine in for repair. The machine powers up and goes
through the Operating System upgrade, up to the point the Flash is written
to, where it fails and the unit will not boot, showing a "damaged memory"
warning. I suspect the Flash chip is faulty.

When I informed the owner of my findings, he then tells me he thinks it was
damaged by a PAT test. It is powered by a Wall Wart, and he thinks it was
plugged into the unit during the test, as it stopped working immediately
afterwards.

An internal inspection shows around 10 caps around the internal power
supplies are bulging and have leaked guff onto the PCB. The 3.3v rail is at
over 4 volts, so presumable the regulator is toast.

So, if you PAT test a Wall Wart plugged into a unit and turned on, what is
likely to happen? What I have just described perhaps?
Or did someone just use the wrong power supply instead and isn't letting on?

Cheers,

Gareth.

== 2 of 18 ==
Date: Wed, Jul 27 2011 11:07 am
From: "Wild_Bill"

PAT?

--
Cheers,
WB
.............

"Gareth Magennis" <sound.service@btconnect.com> wrote in message
news:s0YXp.79735$Dk2.59038@newsfe04.ams2...
> Hi,
>
> I have a Roland drum machine in for repair. The machine powers up and
> goes
> through the Operating System upgrade, up to the point the Flash is written
> to, where it fails and the unit will not boot, showing a "damaged memory"
> warning. I suspect the Flash chip is faulty.
>
>
> When I informed the owner of my findings, he then tells me he thinks it
> was
> damaged by a PAT test. It is powered by a Wall Wart, and he thinks it was
> plugged into the unit during the test, as it stopped working immediately
> afterwards.
>
> An internal inspection shows around 10 caps around the internal power
> supplies are bulging and have leaked guff onto the PCB. The 3.3v rail is
> at
> over 4 volts, so presumable the regulator is toast.
>
>
>
> So, if you PAT test a Wall Wart plugged into a unit and turned on, what is
> likely to happen? What I have just described perhaps?
> Or did someone just use the wrong power supply instead and isn't letting
> on?
>
>
>
> Cheers,
>
>
> Gareth.

== 3 of 18 ==
Date: Wed, Jul 27 2011 11:20 am
From: Jeff Liebermann

On Wed, 27 Jul 2011 18:36:27 +0100, "Gareth Magennis"
<sound.service@btconnect.com> wrote:

>An internal inspection shows around 10 caps around the internal power
>supplies are bulging and have leaked guff onto the PCB. The 3.3v rail is at
>over 4 volts, so presumable the regulator is toast.

Regulator might be toast. Or, you might be measuring a fairly high
ripple current because none of the capacitors are working. Measure it
with an oscilloscope to be sure.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

== 4 of 18 ==
Date: Wed, Jul 27 2011 11:23 am
From: Jeff Liebermann

On Wed, 27 Jul 2011 14:07:31 -0400, "Wild_Bill"
<wb_wildbill@XSPAMyahoo.com> wrote:

>PAT?

Portable Appliance Test
<http://en.wikipedia.org/wiki/PAT_Testing>

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

== 5 of 18 ==
Date: Wed, Jul 27 2011 11:30 am
From: "Gareth Magennis"

"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:4ol0379a0u01kimh9u2q2kuh1leiumtffj@4ax.com...
> On Wed, 27 Jul 2011 14:07:31 -0400, "Wild_Bill"
> <wb_wildbill@XSPAMyahoo.com> wrote:
>
>>PAT?
>
> Portable Appliance Test
> <http://en.wikipedia.org/wiki/PAT_Testing>

Should really be PA Test, but nobody would be able to pronounce it.

A bit like PIN number. (IS there a name for these misnamed things?)

Gareth.

== 6 of 18 ==
Date: Wed, Jul 27 2011 11:50 am
From: Jeff Liebermann

On Wed, 27 Jul 2011 19:30:20 +0100, "Gareth Magennis"
<sound.service@btconnect.com> wrote:

>"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
>news:4ol0379a0u01kimh9u2q2kuh1leiumtffj@4ax.com...
>> On Wed, 27 Jul 2011 14:07:31 -0400, "Wild_Bill"
>> <wb_wildbill@XSPAMyahoo.com> wrote:
>>
>>>PAT?
>>
>> Portable Appliance Test
>> <http://en.wikipedia.org/wiki/PAT_Testing>

>Should really be PA Test, but nobody would be able to pronounce it.
>A bit like PIN number. (IS there a name for these misnamed things?)
>Gareth.

Yes. See:
<http://en.wikipedia.org/wiki/RAS_syndrome>

Note that we don't have PAT testers in the USA. As part of our
governments War on Industry, we trust the outsourced manufacturures in
China to produce consumer appliances that electrocute only a modest
number of users. We also enjoy the protection of a litigatory
environment, that inspires massive recalls if one defective appliance
is found on the theory that if one is defective, then the entire
production run is also likely to be defective. We also have various
testing and certification labs, that will guarantee that an appliance
design will not kill the user or initiate a fire, even if the
appliance doesn't work. With these protections in place, there's no
need for PAT testing.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

== 7 of 18 ==
Date: Wed, Jul 27 2011 12:09 pm
From: "Gareth Magennis"

"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:ltm037922tlg0sv176iqem7l6l5s872g3s@4ax.com...
> On Wed, 27 Jul 2011 19:30:20 +0100, "Gareth Magennis"
> <sound.service@btconnect.com> wrote:
>
>>"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
>>news:4ol0379a0u01kimh9u2q2kuh1leiumtffj@4ax.com...
>>> On Wed, 27 Jul 2011 14:07:31 -0400, "Wild_Bill"
>>> <wb_wildbill@XSPAMyahoo.com> wrote:
>>>
>>>>PAT?
>>>
>>> Portable Appliance Test
>>> <http://en.wikipedia.org/wiki/PAT_Testing>
>
>>Should really be PA Test, but nobody would be able to pronounce it.
>>A bit like PIN number. (IS there a name for these misnamed things?)
>>Gareth.
>
> Yes. See:
> <http://en.wikipedia.org/wiki/RAS_syndrome>
>
> Note that we don't have PAT testers in the USA. As part of our
> governments War on Industry, we trust the outsourced manufacturures in
> China to produce consumer appliances that electrocute only a modest
> number of users. We also enjoy the protection of a litigatory
> environment, that inspires massive recalls if one defective appliance
> is found on the theory that if one is defective, then the entire
> production run is also likely to be defective. We also have various
> testing and certification labs, that will guarantee that an appliance
> design will not kill the user or initiate a fire, even if the
> appliance doesn't work. With these protections in place, there's no
> need for PAT testing.
>

Well that's just great, Jeff!

In the UK we expect cheap crap to break, and to subsequently kill people.
The fact that it never really has doesn't stop our enthusiasm for Health And
Safety in spades.

Thanks for the RAS syndrome link.
I've always chuckled at the naming of the programming language GNU, the
acronym for "GNU's Not Unix".

Gareth.

== 8 of 18 ==
Date: Wed, Jul 27 2011 4:45 pm
From: "Phil Allison"

"Jeff Liebermann is a Clueless Idiot "
>
> Note that we don't have PAT testers in the USA.

** Shame on you.

> As part of our
> governments War on Industry, we trust the outsourced manufacturures in
> China to produce consumer appliances that electrocute only a modest
> number of users. We also enjoy the protection of a litigatory
> environment, that inspires massive recalls if one defective appliance
> is found on the theory that if one is defective, then the entire
> production run is also likely to be defective. We also have various
> testing and certification labs, that will guarantee that an appliance
> design will not kill the user or initiate a fire, even if the
> appliance doesn't work. With these protections in place, there's no
> need for PAT testing.

** Got NOTHING to do with PAT testing !!!

PAT testing is all about the possibility that electrical equipment may
become unsafe after a period of use, due to wear and tear, accidental damage
and water ingress.

It is only *required* to be done were equipment is of a portable kind and
provided for staff and others to use in a work environment.

For example, hire businesses have to regularly PAT test any electrical items
they rent to folk.

It's an idea dreamt up by bureaucrats - and rather pointless since
electrical faults and damage occur at ANY time and PAT testing does nothing
to prevent that.

.... Phil

== 9 of 18 ==
Date: Thurs, Jul 28 2011 12:26 am
From: "N_Cook"

Gareth Magennis <sound.service@btconnect.com> wrote in message
news:s0YXp.79735$Dk2.59038@newsfe04.ams2...
> Hi,
>
> I have a Roland drum machine in for repair. The machine powers up and
goes
> through the Operating System upgrade, up to the point the Flash is written
> to, where it fails and the unit will not boot, showing a "damaged memory"
> warning. I suspect the Flash chip is faulty.
>
>
> When I informed the owner of my findings, he then tells me he thinks it
was
> damaged by a PAT test. It is powered by a Wall Wart, and he thinks it was
> plugged into the unit during the test, as it stopped working immediately
> afterwards.
>
> An internal inspection shows around 10 caps around the internal power
> supplies are bulging and have leaked guff onto the PCB. The 3.3v rail is
at
> over 4 volts, so presumable the regulator is toast.
>
>
>
> So, if you PAT test a Wall Wart plugged into a unit and turned on, what is
> likely to happen? What I have just described perhaps?
> Or did someone just use the wrong power supply instead and isn't letting
on?
>
>
>
> Cheers,
>
>
> Gareth.
>

Now if a numb-skull used the discrete IEC lead tester, flash-tester, instead
of the more down-to-ground ;-) PAT tester then expect such damage

== 10 of 18 ==
Date: Thurs, Jul 28 2011 1:13 am
From: "Arfa Daily"

"Gareth Magennis" <sound.service@btconnect.com> wrote in message
news:s0YXp.79735$Dk2.59038@newsfe04.ams2...
> Hi,
>
> I have a Roland drum machine in for repair. The machine powers up and
> goes
> through the Operating System upgrade, up to the point the Flash is written
> to, where it fails and the unit will not boot, showing a "damaged memory"
> warning. I suspect the Flash chip is faulty.
>
>
> When I informed the owner of my findings, he then tells me he thinks it
> was
> damaged by a PAT test. It is powered by a Wall Wart, and he thinks it was
> plugged into the unit during the test, as it stopped working immediately
> afterwards.
>
> An internal inspection shows around 10 caps around the internal power
> supplies are bulging and have leaked guff onto the PCB. The 3.3v rail is
> at
> over 4 volts, so presumable the regulator is toast.
>
>
>
> So, if you PAT test a Wall Wart plugged into a unit and turned on, what is
> likely to happen? What I have just described perhaps?
> Or did someone just use the wrong power supply instead and isn't letting
> on?
>
>
>
> Cheers,
>
>
> Gareth.

Over the years, I've seen a lot of items from schools and commercial
premises that have odd microprocessor-y problems, and a recent PAT sticker
on them, so I'm certain in my own mind, that these have suffered damage as a
result of either inept or inappropriate use of a tester. The items in
question, are often boom boxes that are double insulated, and have a
removable figure 8 power lead, so there is absolutely no point in applying
these tests, anyway. As to wall-wart powered stuff, I can't recall ever
seeing an item that may have been damaged in such a way, but if other items
with a similar small power transformer fixed internally can suffer, I don't
see why it shouldn't also be the case for an externally powered device. I
think, however, with the bulging caps you say you've found, in this case
it's probably either a wrong power supply having been used, or just general
failure, rather than a PAT issue. Is it from a school ? If it is, it's
probably either left on all the time, or subject to dopey kids and teachers
digging it out of a cupboard in the music room, and jamming in the first
power connector that fits, and appears to make it work ...

Arfa

== 11 of 18 ==
Date: Thurs, Jul 28 2011 2:04 am
From: "Gareth Magennis"

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:FS8Yp.65819$Sr.16865@newsfe12.ams2...
>
>
> "Gareth Magennis" <sound.service@btconnect.com> wrote in message
> news:s0YXp.79735$Dk2.59038@newsfe04.ams2...
>> Hi,
>>
>> I have a Roland drum machine in for repair. The machine powers up and
>> goes
>> through the Operating System upgrade, up to the point the Flash is
>> written
>> to, where it fails and the unit will not boot, showing a "damaged memory"
>> warning. I suspect the Flash chip is faulty.
>>
>>
>> When I informed the owner of my findings, he then tells me he thinks it
>> was
>> damaged by a PAT test. It is powered by a Wall Wart, and he thinks it
>> was
>> plugged into the unit during the test, as it stopped working immediately
>> afterwards.
>>
>> An internal inspection shows around 10 caps around the internal power
>> supplies are bulging and have leaked guff onto the PCB. The 3.3v rail is
>> at
>> over 4 volts, so presumable the regulator is toast.
>>
>>
>>
>> So, if you PAT test a Wall Wart plugged into a unit and turned on, what
>> is
>> likely to happen? What I have just described perhaps?
>> Or did someone just use the wrong power supply instead and isn't letting
>> on?
>>
>>
>>
>> Cheers,
>>
>>
>> Gareth.
>
> Over the years, I've seen a lot of items from schools and commercial
> premises that have odd microprocessor-y problems, and a recent PAT sticker
> on them, so I'm certain in my own mind, that these have suffered damage as
> a result of either inept or inappropriate use of a tester. The items in
> question, are often boom boxes that are double insulated, and have a
> removable figure 8 power lead, so there is absolutely no point in applying
> these tests, anyway. As to wall-wart powered stuff, I can't recall ever
> seeing an item that may have been damaged in such a way, but if other
> items with a similar small power transformer fixed internally can suffer,
> I don't see why it shouldn't also be the case for an externally powered
> device. I think, however, with the bulging caps you say you've found, in
> this case it's probably either a wrong power supply having been used, or
> just general failure, rather than a PAT issue. Is it from a school ? If it
> is, it's probably either left on all the time, or subject to dopey kids
> and teachers digging it out of a cupboard in the music room, and jamming
> in the first power connector that fits, and appears to make it work ...
>
> Arfa

Thanks Arfa, I was hoping for some real world experience.

This units power supply also has a 2 core mains lead, the 13A plug having a
proper metal pin, so could be mistaken for an earthed unit re: PAT testing.
It is not from a school.

I'm not sure what happens with "inappropriate" PAT testing, hence this post.
I was wondering if a high voltage was able to break through or induced to
the secondary winding to zap the unit in question if it was plugged in and
turned on.

As for the bulging caps, it would surely take some power to do this, which I
guess could not come from a PAT tester, though if they were zapped by one,
subsequent use of the unit with its own power supply may cause further
damage?

As per my post, I suspect, like you, this was a "wrong PSU used numpty
error", though any info on the hazards of PAT testing is welcome.

Cheers,

Gareth.

== 12 of 18 ==
Date: Thurs, Jul 28 2011 4:37 am
From: "Phil Allison"

"Arfa Daily is Fucked in the Head "

>
> Over the years, I've seen a lot of items from schools and commercial
> premises that have odd microprocessor-y problems, and a recent PAT sticker
> on them,

** They all have recent PAT stickers !!!!!!!!!!!!!

What a blatant red herring.

> so I'm certain in my own mind,

** You are a man of very uncertain mind.

> that these have suffered damage as a result of either inept or
> inappropriate use of a tester.

** Absolute bollocks.

> The items in question, are often boom boxes that are double insulated, and
> have a removable figure 8 power lead, so there is absolutely no point in
> applying these tests, anyway.

** The reverse is true.

Class 2 items are the most important to PAT test - as they RELY, 100%,
on insulation quality to be safe.

So the leakage test is ESSENTIAL !

> As to wall-wart powered stuff, I can't recall ever seeing an item that may
> have been damaged in such a way, but if other items with a similar small
> power transformer fixed internally can suffer,

** Massive false presumption.

Wot an utter imbecile.

> I don't see ....

** The only correct statement.

AD is an utter IMBECILE.

.... Phil

== 13 of 18 ==
Date: Thurs, Jul 28 2011 4:39 am
From: "Phil Allison"

"Gareth Magennis"

>
> As per my post, I suspect, like you, this was a "wrong PSU used numpty
> error", though any info on the hazards of PAT testing is welcome.
>

**Another, bloody pathetic, WOFT troll.

.... Phil

== 14 of 18 ==
Date: Thurs, Jul 28 2011 5:14 am
From: "Gareth Magennis"

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:99d03qFm7cU1@mid.individual.net...
>
> "Gareth Magennis"
>
>>
>> As per my post, I suspect, like you, this was a "wrong PSU used numpty
>> error", though any info on the hazards of PAT testing is welcome.
>>
>
>
> **Another, bloody pathetic, WOFT troll.
>
>
>
>
> .... Phil
>
>

What a charming man.

OK, I have looked a little deeper into this problem now with a schematic,
and it seems that all the electro caps on both sides of the 3 main regulator
circuits are bursting, as are a few smaller ones dotted about the PCB.
Unless a PAT tester can somehow damage all these caps downline of the
regulators, without blowing the regulators, I now suspect this to be a bad
batch of electrolytics.

The 4.1 volts I measured at the 3.3v regulator is, as Jeff suggested, due to
ten tons of ripple and HF hash. Replacing the 3 on the 3.3v regulator
restores it to 3.3v with a bit of ripple, so this reg is probably OK.

The caps are green Jamicon 105degree types. All 220uF 16v ones have blown,
as have a few 100uF 16v of the same type. All the 10uF 16v ones dotted
about look OK.

What fun.

Gareth.

== 15 of 18 ==
Date: Thurs, Jul 28 2011 5:20 am
From: Geo

On Wed, 27 Jul 2011 18:36:27 +0100, "Gareth Magennis"
<sound.service@btconnect.com> wrote:

>Hi,
>
>I have a Roland drum machine in for repair. The machine powers up and goes
>through the Operating System upgrade, up to the point the Flash is written
>to, where it fails and the unit will not boot, showing a "damaged memory"
>warning. I suspect the Flash chip is faulty.
>
>
>When I informed the owner of my findings, he then tells me he thinks it was
>damaged by a PAT test. It is powered by a Wall Wart, and he thinks it was
>plugged into the unit during the test, as it stopped working immediately
>afterwards.
>
>An internal inspection shows around 10 caps around the internal power
>supplies are bulging and have leaked guff onto the PCB. The 3.3v rail is at
>over 4 volts, so presumable the regulator is toast.
>
>
>
>So, if you PAT test a Wall Wart plugged into a unit and turned on, what is
>likely to happen? What I have just described perhaps?
>Or did someone just use the wrong power supply instead and isn't letting on?

Possibly. In general, wall warts are class II items with no earth pin
so visual inspection is all I would do.
In the (unlikely) event that it was a Class I device with earth pin
and exposed metalwork then a voltage test would be made between line
and the metalwork and a resistance check from metal to earth pin.
I would not test a wall wart with equipment (e.g. printer) connected
as the equipment will be working on low voltage and not be subject to
testing.
I doubt that a short pulse of high voltage would cause caps to bulge
anyway.

== 16 of 18 ==
Date: Thurs, Jul 28 2011 5:39 am
From: "Arfa Daily"

"Phil Allison" <phil_a@tpg.com.au> wrote in message
news:99d00tFli3U1@mid.individual.net...
>
> "Arfa Daily is Fucked in the Head "
>
>>
>> Over the years, I've seen a lot of items from schools and commercial
>> premises that have odd microprocessor-y problems, and a recent PAT
>> sticker on them,
>
>
> ** They all have recent PAT stickers !!!!!!!!!!!!!
>
> What a blatant red herring.
>
>
>> so I'm certain in my own mind,
>
>
> ** You are a man of very uncertain mind.

Ha ! And that from a fuckin' madman like you ???!!! At least I don't need a
psychiatrist and powerful drugs to keep me under control ...

>
>
>> that these have suffered damage as a result of either inept or
>> inappropriate use of a tester.
>
>
> ** Absolute bollocks.
>
>
>> The items in question, are often boom boxes that are double insulated,
>> and have a removable figure 8 power lead, so there is absolutely no point
>> in applying these tests, anyway.
>
>
> ** The reverse is true.
>
> Class 2 items are the most important to PAT test - as they RELY, 100%,
> on insulation quality to be safe.
>
> So the leakage test is ESSENTIAL !
>

Leakage from where to where ?

>
>> As to wall-wart powered stuff, I can't recall ever seeing an item that
>> may have been damaged in such a way, but if other items with a similar
>> small power transformer fixed internally can suffer,
>
> ** Massive false presumption.
>
> Wot an utter imbecile.
>
>
>> I don't see ....
>
>
> ** The only correct statement.
>
> AD is an utter IMBECILE.
>
>
>
> .... Phil
>

And you, Philip, as I and lots of others have told you many times in the
past, are a fat greasy antipodean twat. So unless you can get your sensible
head that you've had for the last few weeks, back on your shoulders and say
something constructive, fuck off back under your rock. And I'll remember
what an IMBECILE I apparently am, next time you need a Marshall manual and
can't get it ... Arsehole ....

Arfa

== 17 of 18 ==
Date: Thurs, Jul 28 2011 7:17 am
From: "Phil Allison"

"Arfa Daily is Fucked in the Head "
>
>
>>> The items in question, are often boom boxes that are double insulated,
>>> and have a removable figure 8 power lead, so there is absolutely no
>>> point in applying these tests, anyway.
>>
>>
>> ** The reverse is true.
>>
>> Class 2 items are the most important to PAT test - as they RELY,
>> 100%, on insulation quality to be safe.
>>
>> So the leakage test is ESSENTIAL !
>>
>
>
> Leakage from where to where ?

** My god - are YOU really a service tech ??

FYI - you asinine pommy fuckwit:

From both the AC supply pins to any exposed metal parts

- including all connectors.
-----------------------------

How can ** ANYONE ** be so fucking dumb to not realise that ??

AD needs a HUGE fucking kick up his fact stinking arse.

An then the fucking cunt needs to retire before he fucking KILLS someone.

WOT A FUCKING ASS !!!!!

.... Phil

== 18 of 18 ==
Date: Thurs, Jul 28 2011 7:19 am
From: "Phil Allison"

"Geo"
>
> Possibly. In general, wall warts are class II items with no earth pin
> so visual inspection is all I would do.

** Then YOU also need a fucking good kick up the ARSE as well !!

The MONSTROUS ignorance of BASIC electrical safety is

FUCKING APPALLING here ........

... Phil

==============================================================================
TOPIC: Connect TV audio output to old stereo amp
http://groups.google.com/group/sci.electronics.repair/t/f9517efe346c55f4?hl=en
==============================================================================

== 1 of 2 ==
Date: Wed, Jul 27 2011 4:46 pm
From: GS

On Jul 26, 9:41 pm, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
> <PlainB...@yawhoo.com> wrote in message
>
> news:nplo2719lrg5jpaghg40ltl8o8bekcb42c@4ax.com...
>
>
>
>
>
> > On Sun, 24 Jul 2011 10:15:13 -0400, Al Moodie <nos...@nospam.com>
> > wrote:
>
> >>Hi,
>
> >>Not sure if this is the correct forum, but it is the only one I am
> >>familiar with.
>
> >>I have an old audio system, Technics SU 8022 stereo amp attached to
> >>large quaulity technics speakers, works fine.
> >>Have a Sony Bravia LCD TV which has an audio output socket which I use
> >>for headphones occasionally.
> >>Does it make sense to attempt to connect the TV's audio output to the
> >>Technics amp to get better sound quality.
>
> >>Sony TV Audio out:
> >>500mVrms (100% modulation)
> >>More than 1 Vrms at max volume setting
> >>Impedance 47k ohms
>
> >>Technics amp input:
> >>Phono 2.5mV 47k ohm
> >>Aux 150mV 27k ohm
>
> >>I assume I will need some kind of voltage/impedance matching between
> >>the two units.
>
> >>Al Moodie.
> > There are several issues.
>
> >  First of all, do not use the phono input; it is designed for a
> > magnetic cartridge, has RIAA equilization, and will seriously
> > overamplify the bass frequencies.
>
> >  Second, I would spend some time reading the manual for the TV, and
> > studying the function of the audio output RCA jacks.  If they can be
> > configured to suit your purposes, they would be preferable to the
> > headphone jack.
>
> >  Third, you are setting up a situation where the TV will be turned
> > off, but the amplifier will still be on.  For a number of reasons,
> > this is not desirable.
>
> > PlainBill
>
> My AV amp stays on all the time, and it doesn't cause me any problems ...
>
> Arfa

I got a couple pseudo theater amps that shut down with no input. I
also think some active subwoofers also shut Down.

Greg

== 2 of 2 ==
Date: Thurs, Jul 28 2011 1:20 am
From: "Arfa Daily"

"GS" <zekor@comcast.net> wrote in message
news:763bc8c2-4d1b-4913-8a2a-d9d2fd322e4c@t5g2000yqj.googlegroups.com...
> On Jul 26, 9:41 pm, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
>> <PlainB...@yawhoo.com> wrote in message
>>
>> news:nplo2719lrg5jpaghg40ltl8o8bekcb42c@4ax.com...
>>
>>
>>
>>
>>
>> > On Sun, 24 Jul 2011 10:15:13 -0400, Al Moodie <nos...@nospam.com>
>> > wrote:
>>
>> >>Hi,
>>
>> >>Not sure if this is the correct forum, but it is the only one I am
>> >>familiar with.
>>
>> >>I have an old audio system, Technics SU 8022 stereo amp attached to
>> >>large quaulity technics speakers, works fine.
>> >>Have a Sony Bravia LCD TV which has an audio output socket which I use
>> >>for headphones occasionally.
>> >>Does it make sense to attempt to connect the TV's audio output to the
>> >>Technics amp to get better sound quality.
>>
>> >>Sony TV Audio out:
>> >>500mVrms (100% modulation)
>> >>More than 1 Vrms at max volume setting
>> >>Impedance 47k ohms
>>
>> >>Technics amp input:
>> >>Phono 2.5mV 47k ohm
>> >>Aux 150mV 27k ohm
>>
>> >>I assume I will need some kind of voltage/impedance matching between
>> >>the two units.
>>
>> >>Al Moodie.
>> > There are several issues.
>>
>> > First of all, do not use the phono input; it is designed for a
>> > magnetic cartridge, has RIAA equilization, and will seriously
>> > overamplify the bass frequencies.
>>
>> > Second, I would spend some time reading the manual for the TV, and
>> > studying the function of the audio output RCA jacks. If they can be
>> > configured to suit your purposes, they would be preferable to the
>> > headphone jack.
>>
>> > Third, you are setting up a situation where the TV will be turned
>> > off, but the amplifier will still be on. For a number of reasons,
>> > this is not desirable.
>>
>> > PlainBill
>>
>> My AV amp stays on all the time, and it doesn't cause me any problems ...
>>
>> Arfa
>
> I got a couple pseudo theater amps that shut down with no input. I
> also think some active subwoofers also shut Down.
>
> Greg

Mine, however, is a 5.1 Sony home cinema amp with built in DVD (that I don't
use), and remains fully powered with or without input. I am, however, fully
familiar with the types that do shut down. I have repaired two in the last
three weeks.

Arfa

==============================================================================
TOPIC: Sony TV
http://groups.google.com/group/sci.electronics.repair/t/b4ecbdbddd551e09?hl=en
==============================================================================

== 1 of 1 ==
Date: Wed, Jul 27 2011 7:23 pm
From: John-Del

On Jul 27, 10:46 am, "Vince Schmitt" <vschmit...@gmail.com> wrote:
> Hi!
> Sony TV KDL 40S4100
> How much voltage should be on the bridge rectifier? The relay clicks and
> nothing happens.
>                Thanks for any info I can get.
>                                            Vince

If you're reading it right at the AC bridge, expect 160VDC for 120VAC
in.

==============================================================================

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