In message , J. Mc Laughlin
writes
There is more to the Franklin rods used in England: George III is said to
have required the ends to be converted to round from pointed when the
Revolution started - a pointed slam at Dr. Franklin. Nevertheless, the
houses (once there were two) of parliament were protected by Dr. Franklin's
rods.

It would have been so easy for the English to have co-opted Dr. Franklin
and quite changed the course of history. Instead, he conned the French out
of the critical support needed to win our freedom. 73 Mac N8TT

--
J. Mc Laughlin; Michigan U.S.A.
Home:



Very interesting! However the American Benjamin Franklin's pointed
lightning rods (it was not a British design) was never scientifically
challenged until a couple of years ago. Scientists have now shown that
blunt-tipped air terminals are attached by lightning with significantly
higher frequency than sharp tipped rods are. Pretty amazing that it took
over 230 years to "discover" this! So scrap the concept that a sharp edge
attracts charges, at least it does not attract lighting, the ultimate
charge.


http://www.usatoday.com/weather/reso...ghtn-rod-tests
.htm
http://www.esdjournal.com/articles/f...n/franklin.htm
http://www.mikeholt.com/news/archive...tningblunt.htm
etc, etc

Jack Painter
Virginia Beach VA




In message , J. Mc Laughlin
writes
There is more to the Franklin rods used in England: George III is said to
have required the ends to be converted to round from pointed when the
Revolution started - a pointed slam at Dr. Franklin. Nevertheless, the
houses (once there were two) of parliament were protected by Dr. Franklin's
rods.

It would have been so easy for the English to have co-opted Dr. Franklin
and quite changed the course of history. Instead, he conned the French out
of the critical support needed to win our freedom. 73 Mac N8TT

--
J. Mc Laughlin; Michigan U.S.A.
Home:



'Protected' is the word. What is not always appreciated is that the
primary purpose of lightning rods (usually called 'lightning conductors'
in the UK) is to PREVENT a strike by allowing the electrical charge to
leak away before sufficient voltage builds up to cause an actual strike.
Ian.
--

Richard Harrison wrote:
Ian White, G3SEK wrote:
"---but not a cage."

A cage according to my American dictionary is:
"A boxlike receptacle or enclosure for confining birds or other animals,
made with openwork of wires, bars, etc."

Ian sent me to my dictionary of electronics which reads:
"Faraday cage-See Faraday Shield"

Usage varies from place to place. I don`t know if I`m vindicated or
stand corrected.

Me neither! The main lesson is that we have to be careful to define what
we mean, because there's a strong risk that other people might
understand something different.

Faraday cages are used at CERN and other large particle accelerators, to
keep the sensitive particle detectors isolated from the pulsed megawatts
of RF energy that are kicking the particles around the ring. CERN is an
international facility, so each country has its own experiments using
separate Faraday cages.

Several years ago, I needed to call a friend who was working at CERN.
Someone picked up the phone, and a voice said "British Cage".

"Well," I thought, "that certainly puts us in our place..."


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

"Julia Child" wrote in message
...
What's with all the recipe bull**** posts?

Who's posting these?

Ed Price wrote:


SNIP

No, I didn't write that. However, "Julia", rest assured that, by posting
your question, your address will soon be harvested for use by the Hipcrime
bot in the DOS attack. Don't reply, don't post about it, don't help the bot.

Ed
wb6wsn

"Gary Schafer" wrote
Jack,

All three references are of the same article. Note the rebuttals at
the end of one of them.

I would also find it hard to believe that ANY rods on a 12000 foot
mountain were not hit in 7 years!

That study would suggest that pointed rods were excellent lightning
repellers and would protect things from being struck. Exactly what
Franklin first thought.

If not excellent repellers then it would be highly suspect of the
placement of the pointed rods on the mountain.

73
Gary K4FMX

Hi Gary, the study is of course much more detailed than the articles
describe, I'll see if I can find you a link or post the abstract here
anyway. But no, there is absolutely no such conclusion in that study (or any
other accepted work) that any device can prevent lightning from striking a
particular point by "draining off" charges.

73,
Jack

"Ian Jackson" wrote
'Protected' is the word. What is not always appreciated is that the
primary purpose of lightning rods (usually called 'lightning conductors'
in the UK) is to PREVENT a strike by allowing the electrical charge to
leak away before sufficient voltage builds up to cause an actual strike.
Ian.

Hi Ian, while Franklin originally thought this was the case, he and others
soon realized that safe handling of a lightning attachment was the function
of his Franklin Rods, NOT avoidance of attachment. There has never been any
proof that any device can prevent a strike from attaching to a particular
point. The controversy surrounding the CTS (Charge Transfer System) and ESE
(Early Streamer Emitters) exposes some of the dumbest junk science ever to
hit the lightning-rod snake-oil trail. It has been thoroughly discredited as
having absolutely zero effectiveness as a preventer and limited usefulness
as a standard Franklin Rod when installed as its snake-oil purveyors
proscribe. So please never assume that any rod, termination device,
voodoo-doll on the roof or anything else can have any affect whatsoever of
preventing a strike from attaching at any particular point.

Jack Painter
Virginia Beach, Virginia

In message QkAAd.35660$7p.12710@lakeread02, Jack Painter
writes

"Ian Jackson" wrote
'Protected' is the word. What is not always appreciated is that the
primary purpose of lightning rods (usually called 'lightning conductors'
in the UK) is to PREVENT a strike by allowing the electrical charge to
leak away before sufficient voltage builds up to cause an actual strike.
Ian.

Hi Ian, while Franklin originally thought this was the case, he and others
soon realized that safe handling of a lightning attachment was the function
of his Franklin Rods, NOT avoidance of attachment. There has never been any
proof that any device can prevent a strike from attaching to a particular
point. The controversy surrounding the CTS (Charge Transfer System) and ESE
(Early Streamer Emitters) exposes some of the dumbest junk science ever to
hit the lightning-rod snake-oil trail. It has been thoroughly discredited as
having absolutely zero effectiveness as a preventer and limited usefulness
as a standard Franklin Rod when installed as its snake-oil purveyors
proscribe. So please never assume that any rod, termination device,
voodoo-doll on the roof or anything else can have any affect whatsoever of
preventing a strike from attaching at any particular point.

Jack Painter
Virginia Beach, Virginia



As I said, I WAS scraping the very bottoms of the memory banks (and
licking them clean as well).....
Ian.
--

Wasn't Franklin that lunatic who used to walk around flying kites in the
middle of thunderstorms? And he now gets praised for it!

"Richard Clark" wrote in message
...
On Sat, 11 Dec 2004 14:11:44 -0800, "Ed Price"
wrote:

You
are asking him to allow a potentially dangerous device to be operated
just
for your convenience and entertainment. Switch roles for just a
minute.

Why is an AM/FM radio receiver potentially more dangerous than laptop PCs,
gameboys, DVD players, and other electronic devices that are used quite
routinely on airplanes?

"Robert Baer" wrote in message
...
"Faraday shield" to some degree is a myth.

I'd say it's more a case of people tending to think that various metal
structures such as cars, airplnes, metal boxes, etc. are close to ideal
'Faraday shields' when, in actuality, they might only be a poor
approximation. (It's this line of reasoning that usually flummuxes people
when they try to shield a monitor that has a wavvy display from some
extneral field with a steel box and find it's not very effective.)

I have seen radars inside quonset huts track a *bird* flying a few
miles away (thru the metal wall)!

Hmm... any idea if the folks inside weren't being exposed to far more
radiation that what we'd typically consider safe? :-)

---Joel Kolstad

"Reg Edwards" wrote

Wasn't Franklin that lunatic who used to walk around flying kites in the
middle of thunderstorms? And he now gets praised for it!

That was an experiment thousands of schoolteachers must dread, or rather
that it actually made the schoolbooks and includes artist renderings, in
case enterprising young minds wish to recreate this "experiment".
Frightening thought how many may have actually tried it, eh? ;-)

73,
Jack
Va Bch