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Old June 9th 12, 10:32 PM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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Default Automotive body filler electrical characteristics

On Sat, 09 Jun 2012 13:20:26 -0700, Jeff Liebermann
wrote:

Not exactly. A water soaked insulator is certain a potential problem.
Yet, there are perfectly usable insulators that contain water. For
example, concrete, bricks, and some pottery are contain considerable
water, but are tolerable insulators, especially if glazed. HF has no
effect on the water because there is insufficient energy at 2-30MHz to
convince the water molecule to vibrate. The higher the frequency, the
higher the energy:
E = Plank's-constant * speed-o-light / wavelength
While building an HF antenna structure out of bricks is feasible, I
would not suggest you place a brick in a microwave oven. It will get
hot and eventually crumble as the water evaporates.


Well, I lied. Apparently it only gets hot and does not crumble:
http://www.youtube.com/watch?v=aCRBeo2hsmU
(7 mins). This has to be the most boring YouTube video ever. However,
watching the author get burned by the brick when he tries to remove
the brick from the oven is priceless.

Also, not that power line insulators are quite hygroscopic (absorbs
moisture). The surface glazing is a good moisture barrier so the
insulator insides remain quite dry. However, even a small crack in
the glazing will eventually introduce enough water into the inside to
cause arcing.

Please re-read my summor of the contents from the MSDS sheets.


Oops... that should be "summary".


--
Jeff Liebermann
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Skype: JeffLiebermann AE6KS 831-336-2558