TV on a dimmer switch?!?
 

Hiya everyone,

I have an interesting one for all of you. My wife does improv comedy at a
local bar in my area. In one of her conversations with the owner, she
mentioned that I was "into" eletronics. He asked her if she would have me
look at two of his televisions that aren't working.

Generally I shy away from "favors" such as this. But, when she told me the
story of what happened to the TV's I got curious.

Apparently he plugged in the sets on a wall circuit that is on a dimmer for
the overhead lights. Needless to say, the TV's didn't like that very much
when the lights were dimmed. They both now give that neat "click click
click" when turned on.

Now I do work on electronics, but computer based for the most part. Monitors
are very close to televisions and that clicking usually means the MOSFET is
not firing the flyback. Would this be the same for these televisions?

The sets are both Sharp 25K-M100. Any info (or "witty jibes" at plugging in
two TV's on a dimmer circuit) would be appreciated.

Take care,


Tofer

Most likely the power supply, and scan circuits are damaged. This will
involve a number of parts to be changed. This type of repair can be
expensive.

--

Jerry G.
==========================


"Tofer" wrote in message
...
Hiya everyone,

I have an interesting one for all of you. My wife does improv comedy at a
local bar in my area. In one of her conversations with the owner, she
mentioned that I was "into" eletronics. He asked her if she would have me
look at two of his televisions that aren't working.

Generally I shy away from "favors" such as this. But, when she told me the
story of what happened to the TV's I got curious.

Apparently he plugged in the sets on a wall circuit that is on a dimmer for
the overhead lights. Needless to say, the TV's didn't like that very much
when the lights were dimmed. They both now give that neat "click click
click" when turned on.

Now I do work on electronics, but computer based for the most part. Monitors
are very close to televisions and that clicking usually means the MOSFET is
not firing the flyback. Would this be the same for these televisions?

The sets are both Sharp 25K-M100. Any info (or "witty jibes" at plugging in
two TV's on a dimmer circuit) would be appreciated.

Take care,


Tofer

"Ross Herbert" wrote in message
...
On Mon, 30 Aug 2004 19:54:14 -0700, "Tofer"
wrote:

|Hiya everyone,
|
|I have an interesting one for all of you. My wife does improv comedy at a
|local bar in my area. In one of her conversations with the owner, she
|mentioned that I was "into" eletronics. He asked her if she would have me
|look at two of his televisions that aren't working.
|


Plugging even one TV into a socket controlled by a dimmer is the
dumbest idea I ever heard. What would be the purpose of doing this,
unless it was accidental as appears to be the case here?

Why isn't the dimmer controlled outlet a different type of socket to
the general purpose ones? This way the TV can't be plugged into a
normal outlet.

What would you expect? This club owner works in the "Entertainment
Industry" and those people are usually incapable of anything more
complicated than operating a doorknob or unrolling toilet paper. Look at
the dingbats on that television show "Last Comic Standing". If those
self-styled "comics" couldn't memorize their 8 or 9 lines, their next
alternative employment would be selling newspapers on an intersection.

I do like mimes though. Can't get enough of their "trapped in a box" and
"pulling a rope" routine. I predict that there will be a mime show on NBC
next summer, sandwiched between "Fear Factor - Families" and "Law & Order:
Parking Violators". Potential names for a mime breakthrough program would
include "Mime Field: Blown Away" and "Easy on My Mime!"

Oh yes, I think the two televisions are FUBAR. As the French would say
"they are junque".

The owner had a "certified" electrician install several light racks to
illuminate some new pictures he had put on the wall. From what I can tell,
this bozo electrician found the nearest circuit and tapped into it.
Naturally not thinking far enough ahead to check for outlets and other
devices on that circuit. The dimmer was put in just a few feet off the main.
Basicly, he took an entire 50' wall and put it on one dimmer.

Thanks for all the responses. I had not thought of damage to the PSU the way
you described Ross. That sounds very much like the culprit. I have not
physically looked at the sets yet. That I will do tomorrow sometime.
However, I do agree with the FUBAR. Or as we said in the USAF, NRTS it.

Mimes?? Think I will suggest to my wife that she "mime" for her next act.
Then again, keeping her mouth shut is not her strongest area.


Shhhhhhhh... don't tell her I said that ;)


Thanks again for the input, Cheers.


Tofer


"Jerry G." wrote in message
...
Most likely the power supply, and scan circuits are damaged. This will
involve a number of parts to be changed. This type of repair can be
expensive.

--

Jerry G.
==========================


"Tofer" wrote in message
...
Hiya everyone,

I have an interesting one for all of you. My wife does improv comedy at a
local bar in my area. In one of her conversations with the owner, she
mentioned that I was "into" eletronics. He asked her if she would have me
look at two of his televisions that aren't working.

Generally I shy away from "favors" such as this. But, when she told me the
story of what happened to the TV's I got curious.

Apparently he plugged in the sets on a wall circuit that is on a dimmer
for
the overhead lights. Needless to say, the TV's didn't like that very much
when the lights were dimmed. They both now give that neat "click click
click" when turned on.

Now I do work on electronics, but computer based for the most part.
Monitors
are very close to televisions and that clicking usually means the MOSFET
is
not firing the flyback. Would this be the same for these televisions?

The sets are both Sharp 25K-M100. Any info (or "witty jibes" at plugging
in
two TV's on a dimmer circuit) would be appreciated.

Take care,


Tofer

Ross Herbert wrote:
On Mon, 30 Aug 2004 19:54:14 -0700, "Tofer"
wrote:

Hiya everyone,

I have an interesting one for all of you. My wife does improv comedy
at a local bar in my area. In one of her conversations with the
owner, she mentioned that I was "into" eletronics. He asked her if
she would have me look at two of his televisions that aren't
working.

Generally I shy away from "favors" such as this. But, when she told
me the story of what happened to the TV's I got curious.

Apparently he plugged in the sets on a wall circuit that is on a
dimmer for the overhead lights. Needless to say, the TV's didn't
like that very much when the lights were dimmed. They both now give
that neat "click click click" when turned on.

Now I do work on electronics, but computer based for the most part.
Monitors are very close to televisions and that clicking usually
means the MOSFET is not firing the flyback. Would this be the same
for these televisions?

When initially switched on the power supply sees a light load
momentarily and some devices such as relays will operate even with the
dimmer supplying a fairly low voltage. Once the circuits start to load
down the PSU it just can't supply the required current to keep
everything running and the DC output voltages sag and let the relays
drop out. It may also be that the PSU goes into current limiting mode
and simply switches off and then back on. This can repeat endlessly.

The sets are both Sharp 25K-M100. Any info (or "witty jibes" at
plugging in two TV's on a dimmer circuit) would be appreciated.


Plugging even one TV into a socket controlled by a dimmer is the
dumbest idea I ever heard. What would be the purpose of doing this,
unless it was accidental as appears to be the case here?

I did sound for my daughter's elementry school benefit. They dragged out
their brand new P.A. mixer/amp, plugged it into one channel of the stage
light dimmers and pronounced everything 'set up.'

I raced home to get an extension cord, and a speaker snake so that I could
move the unit at least a few feet out in front of the speakers. The guy who
had plugged it up seemed offended. They 'always did it that way.' Even
though I had shown him the obvious difference in sound when done 'that way,'
he was barely mollified. 'It works' was all he could say. Maybe he
couldn't tell the difference. I suspect they went right back to doing it
'that way' after the event.

BTW, many comments on the 'excellent' sound after the show from the generous
scattering of professionals in the crowd...this 'is' Nashville, after all.

jak


Why isn't the dimmer controlled outlet a different type of socket to
the general purpose ones? This way the TV can't be plugged into a
normal outlet.

I know a guy who did some wiring in my neighbors house. The "electrician"
(using the term very loosely) is a couple cans shy of a 6 pack. Quite a few
around here know him to have no regard to other's property. I'm still
waiting for the house to go up in smoke. As far as I know, this guy is NOT
a licensed electrician. The guy who did the wiring on that track, may in
fact may not have been an "electrician". Those kinds of stunts give those
with the knowledge and skill a bad name as many tend to lump them all
together. Same for Mechanics, Electronics techs, etc....... When I "know"
they aren't skilled, I don't class them with those who are. I just plain
call them idiots. Wannabe's.............. Like quack doctors.

NS

"Tofer" wrote in message
...
The owner had a "certified" electrician install several light racks to
illuminate some new pictures he had put on the wall. From what I can tell,
this bozo electrician found the nearest circuit and tapped into it.
Naturally not thinking far enough ahead to check for outlets and other
devices on that circuit. The dimmer was put in just a few feet off the
main.
Basicly, he took an entire 50' wall and put it on one dimmer.

Thanks for all the responses. I had not thought of damage to the PSU the
way
you described Ross. That sounds very much like the culprit. I have not
physically looked at the sets yet. That I will do tomorrow sometime.
However, I do agree with the FUBAR. Or as we said in the USAF, NRTS it.

Mimes?? Think I will suggest to my wife that she "mime" for her next act.
Then again, keeping her mouth shut is not her strongest area.


Shhhhhhhh... don't tell her I said that ;)


Thanks again for the input, Cheers.


Tofer


"Jerry G." wrote in message
...
Most likely the power supply, and scan circuits are damaged. This will
involve a number of parts to be changed. This type of repair can be
expensive.

--

Jerry G.
==========================


"Tofer" wrote in message
...
Hiya everyone,

I have an interesting one for all of you. My wife does improv comedy at
a
local bar in my area. In one of her conversations with the owner, she
mentioned that I was "into" eletronics. He asked her if she would have
me
look at two of his televisions that aren't working.

Generally I shy away from "favors" such as this. But, when she told me
the
story of what happened to the TV's I got curious.

Apparently he plugged in the sets on a wall circuit that is on a dimmer
for
the overhead lights. Needless to say, the TV's didn't like that very
much
when the lights were dimmed. They both now give that neat "click click
click" when turned on.

Now I do work on electronics, but computer based for the most part.
Monitors
are very close to televisions and that clicking usually means the MOSFET
is
not firing the flyback. Would this be the same for these televisions?

The sets are both Sharp 25K-M100. Any info (or "witty jibes" at plugging
in
two TV's on a dimmer circuit) would be appreciated.

Take care,


Tofer

"Tofer" schreef in bericht
...
Hiya everyone,

I have an interesting one for all of you. My wife does improv comedy at a
local bar in my area. In one of her conversations with the owner, she
mentioned that I was "into" eletronics. He asked her if she would have me
look at two of his televisions that aren't working.

Generally I shy away from "favors" such as this. But, when she told me the
story of what happened to the TV's I got curious.

Apparently he plugged in the sets on a wall circuit that is on a dimmer
for
the overhead lights. Needless to say, the TV's didn't like that very much
when the lights were dimmed. They both now give that neat "click click
click" when turned on.

Now I do work on electronics, but computer based for the most part.
Monitors
are very close to televisions and that clicking usually means the MOSFET
is
not firing the flyback. Would this be the same for these televisions?

The sets are both Sharp 25K-M100. Any info (or "witty jibes" at plugging
in
two TV's on a dimmer circuit) would be appreciated.

Take care,


Tofer




Like most computer monitors, TVs are powered by an SMPS these days. Most
likely the clicking comes from that SMPS. It tries to start but as the
MOSFET is gone or there is a short (or overload) somewhere else in the set,
it switches off quickly again. Except for the SMPSs MOSFET, the HOT is also
suspect like you mentioned.

petrus bitbyter


---
Outgoing mail is certified Virus Free.
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It all depends on the type of power supply TV has. Nothing may go
wrong with some of the TVs when put in to a dimmer socket, it also
depends on how dim the dimmer is set. Most likely this TV doesn't use
a general type of SMPS.
What I mean by general type is that there would be fuse and some
protection circuit (surge suppressor, varistor, few coils) and then a
bridge rectifier on the supply input side. If this is the case why
anything go wrong unless dimmer sets the voltage too low and SMPS try
hard to boost it up.... and fail.

I am curious to know if anything go wrong with dimmer? Most of the
dimmers are good only for Resistive loads.

I successfully run a PC with ~300V DC which is actually designed to
run at 230V AC 50Hz.

-Suraj


"Tofer" wrote in message ...
Hiya everyone,

I have an interesting one for all of you. My wife does improv comedy at a
local bar in my area. In one of her conversations with the owner, she
mentioned that I was "into" eletronics. He asked her if she would have me
look at two of his televisions that aren't working.

Generally I shy away from "favors" such as this. But, when she told me the
story of what happened to the TV's I got curious.

Apparently he plugged in the sets on a wall circuit that is on a dimmer for
the overhead lights. Needless to say, the TV's didn't like that very much
when the lights were dimmed. They both now give that neat "click click
click" when turned on.

Now I do work on electronics, but computer based for the most part. Monitors
are very close to televisions and that clicking usually means the MOSFET is
not firing the flyback. Would this be the same for these televisions?

The sets are both Sharp 25K-M100. Any info (or "witty jibes" at plugging in
two TV's on a dimmer circuit) would be appreciated.

Take care,


Tofer

(Suraj Singh) writes:

It all depends on the type of power supply TV has. Nothing may go
wrong with some of the TVs when put in to a dimmer socket, it also
depends on how dim the dimmer is set. Most likely this TV doesn't use
a general type of SMPS.
What I mean by general type is that there would be fuse and some
protection circuit (surge suppressor, varistor, few coils) and then a
bridge rectifier on the supply input side. If this is the case why
anything go wrong unless dimmer sets the voltage too low and SMPS try
hard to boost it up.... and fail.

I am curious to know if anything go wrong with dimmer? Most of the
dimmers are good only for Resistive loads.

I successfully run a PC with ~300V DC which is actually designed to
run at 230V AC 50Hz.

Not surprising. As you note, the SMPS first rectifies the AC to produce
a bit over 300 VDC. :)

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Why isn't the dimmer controlled outlet a different type of socket to
the general purpose ones? This way the TV can't be plugged into a
normal outlet.

That way lamps wouldn't be able to be plugged in either. Dimmer controlled
outlets are fairly common, they should be labeled though but mistakes
happen.