Antenna reception theory
Roy Lewallen, W7EL wrote:
"A short while ago, I explained why your Faraday cage doesn`t separate E
and H as you claim."
There are many examples of Faraday screens at work removing the E field
while allowing H field coupling. I chose the Faraday sdreens in medium
wave broadcasting used to reduce radiation of harmonics of the channel
frequency.
More numerous examples abound. These are the Faraday screens used in
isolation power transformers between primary and secindary coils to
prevent transient high-frequency energy coupling.
My 19th edition of the ARRL Antenna Book contains yet another example on
page 14-2 which says:
"Fig 2 - Shielded loop for direction finding.
The ends of the shielding turn are not connected, to prevent shielding
the loop from magnetic fields. The shield is effective against electric
fields.
Best regards, Richard Harrison, KB5WZI
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