Re: Soon to arrive my HDTV

"w_tom" <w_tom1@[EMAIL PROTECTED]
> wrote in message 
news:e219271b-ef4f-401b-827c-48a9caef7723@[EMAIL PROTECTED]
> On Mar 26, 9:57 pm, G-squared <stratu...@[EMAIL PROTECTED]
> wrote:
>> OK, a simple question. How do you protect a device that is only
>> equipped with a 2 wire power cord? Are we to open the TV and re-
>> engineer the power system?
>>
>> My personal belief is a gadget like a Metal Oxide Varistor  ( MOV ) to
>> clamp over-voltage peaks will cover the bulk of problems.
>
>  Why re-engineeer protection that is already inside every TV?  All
> appliances contain protection.  Protection that may be overwhelmed by
> a surge that seeks earth ground.
>
>  Put an MOV between two AC wire and the MOV does not even see that
> surge.  That surge enters a TV to find earth ground outgoing via some
> other path - ie coax cable, antenna, or some other conductive path. A
> typically destructive surge is not between two AC wires.  Typically
> destructive surge is on one or both AC wires and seeking earth ground.
>
>  If a TV has only two wires and no other electrical connection to
> earth, then no outgoing path;  no surge protector is just as good as
> that MOV.  But materials that conduct static electricity will also
> conduct the typically destructive surge.  Those materials include
> vinyl floor tiles, carpets, concrete, wall paint, etc.  Incoming on AC
> mains; outgoing on what?  Outgoing via the antenna?  Surge has a
> destructive path to earth ground via the TV - with or without an MOV
> on its power cord.  That MOV does nothing to abate the typically
> destructive surge.
>
>  Protection has always been about earthing before surges enter a
> building.  Telcos don't install protectors at their equipment.  CO
> (connected to overhead wires all over town) will suffer maybe 100
> surges during each thunderstorm - and no damage.  CO's locate
> protectors where wires enter a building and as close to earth ground
> as practicable.   To make that protection even better, the telco
> locates electronics up to 50 meters distant from a protector.
> Separation between electronics and protector makes better protection.
> Better earthing makes better protection.
>
>  What makes a protector (MOV or whatever) effective?  A shorter path
> to better earth ground and a much longer separation to electronics.
>
>  Protection is about where surge energy gets dissipated.  An MOV
> between two AC wires does not dissipate the typically destructive
> surge.  An MOV's job is not to stop or absorb surges.  The MOV's job
> is to shunt (clamp, connect, divert) a surge to something that can
> absorb that energy.  Earth ground.  Surges must be dissipated
> harmlessly in earth.
>
>  Earth a typically destructive surge so that protection inside every
> appliance is not overwhelmed. For homeowners, this means one 'whole
> house' protector AND all protectors (including telephone and cable TV)
> connected short ('less than 10 feet') to a single point earth
> ground.   The MOV properly installed connects a surge from each AC
> wire to earth ground.  The MOV does not stop or absorb surges.  The
> effective MOV connects typically destructive surges harmlessly to what
> it wants - earth ground.   An MOV between two AC wires cannot do that.
>
> http://www.harvardrepeater.org/news/lightning.html
>> Well I assert, from personal and broadcast experience
>> spanning 30 years, that you can design a system that will
>> handle *direct lightning strikes* on a routine basis. It takes
>> some planning and careful layout, but it's not hard, nor is it
>> overly expensive. At WXIA-TV, my other job, we take direct
>> lightning strikes nearly every time there's a thunderstorm.
>> Our downtime from such strikes is almost non-existant.  The
>> last time we went down from a strike, it was due to a strike
>> on the power company's lines knocking *them* out, ...
>> Since my disasterous strike, I've been campaigning
>> vigorously to educate amateurs that you *can* avoid damage
>> from direct strikes.  The belief that there's no protection from
>> direct strike damage is *myth*. ...
>> The keys to effective lightning protection are surprisingly
>> simple, and surprisingly less than obvious. Of course you
>> *must* have a single point ground system that eliminates all
>> ground loops. And you must present a low *impedance* path
>> for the energy to go. That's most generally a low *inductance*
>> path rather than just a low ohm DC path.

I'm wondering about this device . . .

http://brickwall.com/howwork.htm

Does it look like a good idea or do you think it is simply more smoke and 
mirrors?