I'm not sure if this belongs in this discussion or in one about
computers, but I hope I might get some answers anyway. I am studying
abroad for the year in Spain, and my landlady's boyfriend bought a
brand new Panasonic laptop. He hadn't used a computer very much, so I
was helping show him some of the basics. He asked me if there was a way
to play music through his stereo speakers and I said su just buy a
RCA to stereo jack adapter and plug it into your headphones out and
then into a spare RCA in on the stereo receiver. 2 days later he called
me out into the room to show me that it was working. I left the room
and sometime after this, his sound card fried. He took his computer in
to get warrenty repair, and they told him that it was his fault, and
that they wouldn't reapair it. Something about not being the right
power when he plugged it into the stereo. All along I figured the AUX
RCA in and the headphone out were at the same level, and I still
believe they are. I feel partly responsible, and would like to help him
get his sound card replaced. I wasn't wrong, was I? Although Spanish
customer service doesn't put the customer first (imagine that), does
anyone have any ideas for pleading our case to get his sound card
replaced? Thank you.

Sorry. It wasn't Panasonic. I believe it was Samsung.

You cannot damage a soundcard by connecting its output to the input of a
stereo. Headphone level is, for all practical purposes, the same as line
level, and even if it were not, the worst that would happen is that the
stereo would be too soft or too loud or possibly distorted.

If he plugged it into something that was not an input, the situation is
entirely different, of course.

If the repair place says something about "the wrong power," get them to be
precise and then tell us.

Matt wrote:
Sorry. It wasn't Panasonic. I believe it was Samsung.

Ouch! With Samsung it is always customers fault. You cannot damage an
audio card by plug in it to a receiver. If your friend showed you that
it was working then there is no way it could have been damage by the
receiver. What is a possibility is that your friend have put the laptop
in a place that could have block the cooling vent.

Taking the line out from the sound card, and going in to a sound system
should work properly. The only thing I can think of, is if the sound system
or the power supply in the computer has some type of defect, and caused an
electrical loop between the two units.

When bringing the computer in for warranty service, he should have mentioned
that it stopped working, and not contribute any more information. At the
worse case, he will have to have the sound card replaced. In the case of a
laptop, this may mean a new mother board.

--

Jerry G.
======


"Matt" wrote in message
ups.com...
I'm not sure if this belongs in this discussion or in one about
computers, but I hope I might get some answers anyway. I am studying
abroad for the year in Spain, and my landlady's boyfriend bought a
brand new Panasonic laptop. He hadn't used a computer very much, so I
was helping show him some of the basics. He asked me if there was a way
to play music through his stereo speakers and I said su just buy a
RCA to stereo jack adapter and plug it into your headphones out and
then into a spare RCA in on the stereo receiver. 2 days later he called
me out into the room to show me that it was working. I left the room
and sometime after this, his sound card fried. He took his computer in
to get warrenty repair, and they told him that it was his fault, and
that they wouldn't reapair it. Something about not being the right
power when he plugged it into the stereo. All along I figured the AUX
RCA in and the headphone out were at the same level, and I still
believe they are. I feel partly responsible, and would like to help him
get his sound card replaced. I wasn't wrong, was I? Although Spanish
customer service doesn't put the customer first (imagine that), does
anyone have any ideas for pleading our case to get his sound card
replaced? Thank you.

"Matt" wrote in message
ups.com...
I'm not sure if this belongs in this discussion or in one about
computers, but I hope I might get some answers anyway. I am studying
abroad for the year in Spain, and my landlady's boyfriend bought a
brand new Panasonic laptop. He hadn't used a computer very much, so I
was helping show him some of the basics. He asked me if there was a way
to play music through his stereo speakers and I said su just buy a
RCA to stereo jack adapter and plug it into your headphones out and
then into a spare RCA in on the stereo receiver. 2 days later he called
me out into the room to show me that it was working. I left the room
and sometime after this, his sound card fried. He took his computer in
to get warrenty repair, and they told him that it was his fault, and
that they wouldn't reapair it. Something about not being the right
power when he plugged it into the stereo. All along I figured the AUX
RCA in and the headphone out were at the same level, and I still
believe they are. I feel partly responsible, and would like to help him
get his sound card replaced. I wasn't wrong, was I? Although Spanish
customer service doesn't put the customer first (imagine that), does
anyone have any ideas for pleading our case to get his sound card
replaced? Thank you.



People who accidentally break things by doing something silly are often
notoriously bad at owning up to it. If the shop says it is the customers
fault, it could be that they have found something to back this up - e.g.
burnt components. Get them to verify exacty why they think it is your
friend's fault.. And maybe see if your friend has forgotten to tell you
some details of what happened.



Gareth.



Gareth.

"Jerry G." writes:

Taking the line out from the sound card, and going in to a sound system
should work properly. The only thing I can think of, is if the sound system
or the power supply in the computer has some type of defect, and caused an
electrical loop between the two units.

That's one possibility. Ground loops can cause problems sometimes,
and even fry equipment. Information on ground loops can be found at
http://www.epanorama.net/documents/g...oop/index.html

Defective power supplies can cause damage, but quite rarely.

A perfectly working computer power supply, when computer connected
to ungroudner power outler, can pass through enough "leakage" that
can cause equipment damage on some cases when you make interconnections.

Here is my earilier posting on this (after that answers to your other comments

-- quoted posting starts here --

Newsgroups: rec.audio.tech
Subject: Burned out sound card...
References: . com

"mc" writes:

You cannot damage a soundcard by connecting its output to the input of a
stereo.

Theoretically you should not be able to damage a sound card
by connecting its output to the input of the stereo.
It is for what the line output on the computer is designed for.
It is designed to be connected to the input of stereo or
multimedia speakers.

But in real life there are possibilities to damage soundcard
when making the connection! I have seen that happen and
I know wy it happens.

The problem is the following part in it:
1. The typical audio connectors (3.5 mm jack, RCA) easily
make the connection for the signal conductor before the
signal ground makes contact. This is bad.
2. Equipment are not always completely isolated from electrical
power or securely groundes to same ground potential

The combination of those can cause damaging current going
through the sound cards output and/or hifi equipment line
input on some unfortunate cases.

If one equipment is at considerable different potential than another,
then when you make the connection to other equipment, the potential
between them tries to be the same through the audio cable.
Normally the interconnection cable ground shield does this job
nicely when cables are always connected. But when you insert
the cable to the equipment when it was not initially connected,
unfortuantely the signal wire gets the first connection
before the ground. The potential difference between the equipment
tries to go away through that signal wire connection, causing
a quite high surge to the circuitry on the equipment connected
to the line (surge goes through their input/output circuitry).

The potential difference can be considerable. For example
if a PC is powered from ungrounded 230V AC outlet, you can easily
measure around 110V AC between the PC case and real ground
(there would be nearly 1 mA curent if you short circuit case to ground).
This is caused by the AC mains filter capacitors (few nF capacitors
wires live-ground and neutral-ground, ground being connected
to PC signal ground/case + mains connector ground pin).

If the hifi equipment is grounded (for example tuner connected to
antenna outlet or wired to TV/VCR connected to antenna outlet), then
you can get quite considerable (around 110V) surge coming to the audio
circuitry of the PC and/or hifi equipment. The surge nergy is
determined by the side of filtering capacitors (at worst case you
can have up to nearly 150V positive or negative peak voltage in
relation to ground on the ungrounded PC case and charged to
those filtering capacitors if you make connection exactly at
the mains highes volage peak).
This can damage equipment if not very well protected!

To make connections safely you have the following choises
for methods:

1. Use audio connectors that are guaranteed to make the ground
connction first when plug is inserted and cut is last
when removed. Professional audio applications use XLR
connector that does that.

2. Have all equipment securely grounded together. This makes
sure that there will not be damaging potentials between
equipment. This is used in many professional systems.

3. Make the connections and disconnections only when
all the equipment are not plugged to the mains outlet
and not plugged to antenna outlet. Now every equipment
is "freely floating" and no mains leakage that causes
potential differences (there is still small possibility
of problems caused by ESD)

5. Have all equipment built in such way that they do not
have any potentially dangerous amount of mains leakage.
This means consumer hifi equipment that are
dual-insulated designed originally with ungrounded
power connector. Have all "leaky" equipment powered
through safety isolation transformer. Now there
can be potential differences still, but leakage
capacitances are so low that the nergu stored to
them (the one the causes surge in interconnection)
is so low that do not damage well designed equipment.

6. Use a signal isoltation transformer between your equipment.
An audio line isolation transformer will pass the audio
signal but keeps the ends of the isolator otherwise
isolated (no interconnection of equipment cases and
surge related to it)


Those are the basic techniques for making sure that the
connecting/disconnecting audio cables will not fry equipment.
There are those possibilities. Using any of them should
make the connection safe then there is no fault anywhere.


Note: The following setups not covered by above tips
are also "safe" not to damage on interconnection:
- one dual insulated low leakage equipment and one "leaky" equipment
(typical case: ungrounded PC multimedia speakers and ungrounded):
- one dual insulated low leakage equipment and one grounded equipment
(hifi system not connected to antenna outlet and grounded PC)


Headphone level is, for all practical purposes, the same as line
level, and even if it were not, the worst that would happen is that the
stereo would be too soft or too loud or possibly distorted.

You are absolutely right on this.

If he plugged it into something that was not an input, the situation is
entirely different, of course.

You. You are githt on this. Usually a short time accidental inteconnection
of two line outs together (soundcard output and hifi output) does
not damage anything. I can say usually no damage expected here.

If the repair place says something about "the wrong power," get them to be
precise and then tell us.

-- quoted posting ends here --

When bringing the computer in for warranty service, he should have mentioned
that it stopped working, and not contribute any more information.

That's usually the safest way to avoid somebody claiming that
you did something wrong/stupid. IE. It was your mistake.

At the
worse case, he will have to have the sound card replaced. In the case of a
laptop, this may mean a new mother board.

In laptops it is too often replacing motherboard that is expensive.
Usually when the sound card is fried, there is only usually one
IC fried on the motherboard.. but noeadays the computer repairs
the only thign they can do or are allowed to do is just replacing
the whole circuit board instead of doing component level repair
(replace the damaged IC). Doing component level repair on
nowaday's circuit boards packed with small SMD components is hard,
but in most cases doable if you have necessary skill. Depends
on the case if this financially feasible or not. There are case
where component level repairs are done to computer boards.


--

Jerry G.
======


"Matt" wrote in message
ups.com...
I'm not sure if this belongs in this discussion or in one about
computers, but I hope I might get some answers anyway. I am studying
abroad for the year in Spain, and my landlady's boyfriend bought a
brand new Panasonic laptop. He hadn't used a computer very much, so I
was helping show him some of the basics. He asked me if there was a way
to play music through his stereo speakers and I said su just buy a
RCA to stereo jack adapter and plug it into your headphones out and
then into a spare RCA in on the stereo receiver. 2 days later he called
me out into the room to show me that it was working. I left the room
and sometime after this, his sound card fried. He took his computer in
to get warrenty repair, and they told him that it was his fault, and
that they wouldn't reapair it. Something about not being the right
power when he plugged it into the stereo. All along I figured the AUX
RCA in and the headphone out were at the same level, and I still
believe they are. I feel partly responsible, and would like to help him
get his sound card replaced. I wasn't wrong, was I? Although Spanish
customer service doesn't put the customer first (imagine that), does
anyone have any ideas for pleading our case to get his sound card
replaced? Thank you.



--
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at
http://www.epanorama.net/

Wrong power is the best translation I can give... I heard the story
inderectly from my land lady(in Spanish- she said potencía which
translates to power according to my non-engineering dictionary). Next
time I see him, I will ask about it.

Tomi- I understand what you're saying, however would this situation
still fall under fault of the user?? (Should Samsung be responsible for
repairing it??)

In article . com, "Matt" wrote:
I'm not sure if this belongs in this discussion or in one about
computers, but I hope I might get some answers anyway. I am studying
abroad for the year in Spain, and my landlady's boyfriend bought a
brand new Panasonic laptop. He hadn't used a computer very much, so I
was helping show him some of the basics. He asked me if there was a way
to play music through his stereo speakers and I said su just buy a
RCA to stereo jack adapter and plug it into your headphones out and
then into a spare RCA in on the stereo receiver. 2 days later he called
me out into the room to show me that it was working. I left the room
and sometime after this, his sound card fried. He took his computer in
to get warrenty repair, and they told him that it was his fault, and
that they wouldn't reapair it. Something about not being the right
power when he plugged it into the stereo. All along I figured the AUX
RCA in and the headphone out were at the same level, and I still
believe they are. I feel partly responsible, and would like to help him
get his sound card replaced. I wasn't wrong, was I? Although Spanish
customer service doesn't put the customer first (imagine that), does
anyone have any ideas for pleading our case to get his sound card
replaced? Thank you.


If its warrented, then they should fix it, period. An explanation should not have been given
to them of any kind other than it worked for a short time. What do you mean by fried
anyway. Actually burnt?

greg

Here in the USA we have three prong AC outlets.
It is very typical for things like computers to have a real Earth ground
from the chassis to the ground pin in the AC outlet.
It is also very typical for home audio equipment to have only two prongs and
a floating ground.
I have seen some really horrible things happen when a three pronged device
is connected to an amp with a floating ground.

James. )



"Matt" wrote in message
ups.com...
I'm not sure if this belongs in this discussion or in one about
computers, but I hope I might get some answers anyway. I am studying
abroad for the year in Spain, and my landlady's boyfriend bought a
brand new Panasonic laptop. He hadn't used a computer very much, so I
was helping show him some of the basics. He asked me if there was a way
to play music through his stereo speakers and I said su just buy a
RCA to stereo jack adapter and plug it into your headphones out and
then into a spare RCA in on the stereo receiver. 2 days later he called
me out into the room to show me that it was working. I left the room
and sometime after this, his sound card fried. He took his computer in
to get warrenty repair, and they told him that it was his fault, and
that they wouldn't reapair it. Something about not being the right
power when he plugged it into the stereo. All along I figured the AUX
RCA in and the headphone out were at the same level, and I still
believe they are. I feel partly responsible, and would like to help him
get his sound card replaced. I wasn't wrong, was I? Although Spanish
customer service doesn't put the customer first (imagine that), does
anyone have any ideas for pleading our case to get his sound card
replaced? Thank you.

Matt wrote:
Tomi- I understand what you're saying, however would this situation
still fall under fault of the user?? (Should Samsung be responsible for
repairing it??)

I would start with a defective stereo. Fix the problem long before
applying blame. Do this for two reasons - one to fix the problem and
two to learn why the failure happened.

That connection should not have caused damage. And if that
'protection' does fail, then safety grounding of equipment should have
made that failure irrelevant. IOW after suspecting a defective stereo,
then move on to defective building wiring (grounds).

Samsung would have been damaged because too much voltage was applied
to its output - multiple failures had to occur. A better design (ie
Transzorbs, transistors with higher voltages, etc) inside Samsung would
have made damage less likely. But are you going to argue electronics
in court?

First the stereo did something it should not have done. Second,
building grounding also had to fail to let this happen. Both are
described in greater detail by Tomi.

But a laptop should be isolated from the power line ground anyway, shouldn't
it? or not?

In article , "mc" wrote:
But a laptop should be isolated from the power line ground anyway, shouldn't
it? or not?




Not.

"mc" wrote in message


But a laptop should be isolated from the power line
ground anyway, shouldn't it? or not?

I've seen it done both ways - laptops where there was a dead short between
the third pin on the power cord and the laptop chassis, and those where
there was for all intents and purposes an open circuit and even low
capacitance.

I have seen some really horrible things happen when a three pronged
device
is connected to an amp with a floating ground.

Can you give examples of those horrible things you have seen to happen ?



Years ago I was asked to do some electrical work in a bar. I wired up the
light show for the dance floor and some other stuff. They had a really nice
CD juke box and they wanted to hook it into the bar sound system so that it
would play through all of the speakers in the bar. They had an integrated
amp. I think it was Harman Cardin. There was a standard pair of RCA outputs
on the juke box, so I ran cables to the amp and plugged them into the aux
input. That seemed simple enough. When I turned the amp on, it worked. In a
matter of seconds, I noticed an orange glow coming from inside the amp and
then lots of thick white smoke! The sound from the speakers fizzled and
faded. I yanked the amp plug out the wall as fast as I could. I was sure
that the amp was toast. So I figured I didn't have much more to lose at that
point. I unplugged the feeds from the juke box and measured the voltage
between its ground and the amp's ground. I don't remember what it was, but
it wasn't zero. So I took a piece of wire and screwed it to the amp chassis
and screwed the other end to the Earth ground in the AC outlet. I hooked the
juke box back up to the amp and, believe it or not, it worked fine. I still
can't believe what a beating the output transistors took and still survived.
I have never seen a transistor glow orange and smoke and live through it
before or since.

James. )