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S-video on TV, getting zapped

B

Bill

Jan 1, 1970
0
Is it normal to get zapped by the metal shield of this socket when plugged
into the S-video input of a TV? not just a one off either.

This old hos is used specifically for the TV out feature of my video card,
is this going to damage my video card? which is significantly more valuable
than the TV.

More specifically a Sony KV-K29SN21 around 1994 vintage.
 
P

Phil Allison

Jan 1, 1970
0
Peter_purple said:
If these systems are on different power points then its normal if your power
points dont share the same ground, and some dvd, vcr players dont have
a ground anyway, they use a 2 wire live/neutral which is supposed to
be double insulated but they use capacitors from live and neutral to chassis
so they have a leakage current and this builds to a voltage if not grounded.

So get a ground lead connected *FIRST* otherwise you will get some
volts into a logic sugnal - which will *DAMAGE* it !

If there is no ground point on the TV then make sure the shields are
connected first, its common for around 100v or so to 'float' on systems
where there isnt a ground but the current is low so often you dont feel
anything but is enough to cause damage.

This is all asuming your power point has a ground and its the same
ground as your PC and the TV has only a 2-wire plug, do you have a
multimeter ?


** Mr Purple is on the right tram - even if he is unsure of the fare
for the trip !

The answer is simply to use another connector on the TV to ground the set
all the time - possibly just the antenna socket or an audio socket.




........... Phil
 
P

Phil Allison

Jan 1, 1970
0
"Peter_purple" <

Phil Allison wrote:

Say wot ? Whats this depricating implication supposed to be about,


** Cripes, I thought I was being generous to a spastic at Christmas !!!!


If there is one.


** There are always other sockets on a set that has an S-Video connector.


You need to find a proper ground point, some just dont have it.


** Bovine excreta.


You need to make sure the TV ground is the *same* as the
PC output ground,


** See above with runny diarrhoea.



because even if the TV is 'grounded' you can still have
many volts causing the TV out of the PC to get a silent zap making it
useless...



** Who needs LSD when you are "purple" anyhow.




........ Phil
 
P

Peter_purple

Jan 1, 1970
0
Bill said:
Is it normal to get zapped by the metal shield of this socket when plugged
into the S-video input of a TV? not just a one off either.

This old hos is used specifically for the TV out feature of my video card,
is this going to damage my video card? which is significantly more valuable
than the TV.

More specifically a Sony KV-K29SN21 around 1994 vintage.

If these systems are on different power points then its normal if your power
points dont share the same ground, and some dvd, vcr players dont have
a ground anyway, they use a 2 wire live/neutral which is supposed to
be double insulated but they use capacitors from live and neutral to chassis
so they have a leakage current and this builds to a voltage if not grounded.

So get a ground lead connected *FIRST* otherwise you will get some
volts into a logic sugnal - which will *DAMAGE* it !

If there is no ground point on the TV then make sure the shields are
connected first, its common for around 100v or so to 'float' on systems
where there isnt a ground but the current is low so often you dont feel
anything but is enough to cause damage.

This is all asuming your power point has a ground and its the same
ground as your PC and the TV has only a 2-wire plug, do you have a
multimeter ?

--
that is because,

peter purple proclaims

The infamous big dollar scam list of email addresses, growing,
appended here for those nice news bots to collect their email addresses...

[email protected], [email protected], [email protected],

"fprohanp" <[email protected]>, mariam seseseko <[email protected]>,
"GEORGE JOHN" <[email protected]>, "gerald abam"
"tariq ani" <[email protected]>, "Dr. Isa Gambo"
Rebeka Abubakar <[email protected]>, [email protected],
[email protected]
From: "Dr. Ahmed Banigo" <[email protected]>, "Dr. Ahmed Banigo"
"yusuf.mamman" <[email protected]>, [email protected],
[email protected], "kwanta douglas" <[email protected]>,
[email protected],
"TEMBA BAKO NGANBA" <[email protected]>, "mariam abacha"
<[email protected]>
[email protected], [email protected],
[email protected]
 
P

Peter_purple

Jan 1, 1970
0
Phil said:
** Mr Purple is on the right tram - even if he is unsure of the fare
for the trip !

Say wot ? Whats this depricating implication supposed to be about,
can you elaborate what you mean by the fare for the trip, I havent
had a trip for a long long time when I when along for the ride ;) ?
The answer is simply to use another connector on the TV to ground the set
all the time - possibly just the antenna socket or an audio socket.

If there is one.
You need to find a proper ground point, some just dont have it. And you need
to
make sure both grounds are the same potential, hence my question asto
whether you have, or can lay your hands on a multimeter ?
You need to make sure the TV ground is the *same* as the
PC output ground, because even if the TV is 'grounded' you can still have
many volts causing the TV out of the PC to get a silent zap making it
useless...


--
that is because,

peter purple proclaims

The infamous big dollar scam list of email addresses, growing,
appended here for those nice news bots to collect their email addresses...

[email protected], [email protected],
[email protected],
"fprohanp" <[email protected]>, mariam seseseko <[email protected]>,
"GEORGE JOHN" <[email protected]>, "gerald abam"
"tariq ani" <[email protected]>, "Dr. Isa Gambo"
Rebeka Abubakar <[email protected]>, [email protected],
[email protected]
From: "Dr. Ahmed Banigo" <[email protected]>, "Dr. Ahmed Banigo"
"yusuf.mamman" <[email protected]>, [email protected],
[email protected], "kwanta douglas" <[email protected]>,
[email protected],
"TEMBA BAKO NGANBA" <[email protected]>, "mariam abacha"
<[email protected]>
[email protected], [email protected],
[email protected]
 
P

Peter_purple

Jan 1, 1970
0
Phil said:
"Peter_purple" <




** Cripes, I thought I was being generous to a spastic at Christmas !!!!


** There are always other sockets on a set that has an S-Video connector.


** Bovine excreta.


** See above with runny diarrhoea.

because even if the TV is 'grounded' you can still have

** Who needs LSD when you are "purple" anyhow.

....... Phil

have you had a zap or two recently, or are you on accelerated xmas cheer or
hit your noggin on somthun ?



--
that is because,

peter purple proclaims

The infamous big dollar scam list of email addresses, growing,
appended here for those nice news bots to collect their email addresses...

[email protected], [email protected], [email protected],
"fprohanp" <[email protected]>, mariam seseseko <[email protected]>,
"GEORGE JOHN" <[email protected]>, "gerald abam" <[email protected]>,

"tariq ani" <[email protected]>, "Dr. Isa Gambo" <[email protected]>,

Rebeka Abubakar <[email protected]>, [email protected],
[email protected]
From: "Dr. Ahmed Banigo" <[email protected]>, "Dr. Ahmed Banigo"
"yusuf.mamman" <[email protected]>, [email protected],
[email protected], "kwanta douglas" <[email protected]>,
[email protected],
"TEMBA BAKO NGANBA" <[email protected]>, "mariam abacha"
<[email protected]>
[email protected], [email protected],
[email protected]
 
A

Allan

Jan 1, 1970
0
Is it not because most TV sets have a floating Ground, and a PC is Grounded
to Earth?
If you measure the voltage b/t the S Video Gnd and your PC case it may be
around 10 + volts AC.
Its nothing to do with Power points, its just the design of TV sets, Notice
they only have 2 pin AC plug, there is no direct connection to Ground.??

You should NEVER plug in the Svideo lead with your TV set on as there is a
high chance of ZAPPIES...
Allan
 
A

Arpit

Jan 1, 1970
0
Phil, peerhaps you could enlighten me about a similar problem I have.
With my old printer, and current scanner, the USB lead is energised at
what appears to be a reasonably high voltage. if i hold the shell of
the usb lead ( ground) and touch my earthed computer case, or earthed
equaliser, i feel tingling, running the shell over the backs of my
fingers can result in them getting a bit burnt. I can also make teensy
sparks with my finger, same as if I touch the outer shell to my
computer case. WHen i tried to measure thh voltage on the 1000v
setting on my multimeter, it registered 1 for overvoltage. I heard
this is something called capacatative coupling where a voltage is
induced into the chassis. THe (unearthed) scanner uses a cold cathode
tube. THe inverter for such a tube is of a very high frequency, and
high voltage, and can be used to do similar finger tricks with much
greater intensity (outer bit of skin drawing an arc chars, but its
painless) But the printer? the printer was earthed, and I can't think
of any high voltage parts in it, so why would that have been
happening?
 
P

Phil Allison

Jan 1, 1970
0
Arpit said:
Phil, peerhaps you could enlighten me about a similar problem I have.
With my old printer, and current scanner, the USB lead is energised at
what appears to be a reasonably high voltage. if i hold the shell of
the usb lead ( ground) and touch my earthed computer case, or earthed
equaliser, i feel tingling, running the shell over the backs of my
fingers can result in them getting a bit burnt. I can also make teensy
sparks with my finger, same as if I touch the outer shell to my
computer case. WHen i tried to measure thh voltage on the 1000v
setting on my multimeter, it registered 1 for overvoltage. I heard
this is something called capacatative coupling where a voltage is
induced into the chassis. THe (unearthed) scanner uses a cold cathode
tube. THe inverter for such a tube is of a very high frequency, and
high voltage, and can be used to do similar finger tricks with much
greater intensity (outer bit of skin drawing an arc chars, but its
painless) But the printer? the printer was earthed, and I can't think
of any high voltage parts in it, so why would that have been
happening?

** Sounds fascinating.

Can you get a CRO and have a look at the wavefrom ??

Put a resistor - say 10 kohms from the voltage source to ground and
use the CRO to look at the signal across that resistor.





......... Phil
 
A

Arpit

Jan 1, 1970
0
** Sounds fascinating.

Can you get a CRO and have a look at the wavefrom ??

During my search for a CRO some months ago someone pointed me to some
PC oscilloscope software, which actually works reasonably well using
the sound card, so I've been using that ever since. I might try using
an old computer running the software, so if the sound card or computer
gets damaged its no big deal.
Put a resistor - say 10 kohms from the voltage source to ground and
use the CRO to look at the signal across that resistor.

good idea. i'll try that,
thanks,
arpit thomas
 
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