Joe Paulson wrote in a message to All:

 JP> I came across an excellent 2 page article on antennas in
 JP> Scientific American,May,2003  P.89-89
 JP>  
 JP> Describes AM,FM,TV antennas and horizontal,vertical and 
 JP> corkscrew polarizations.
 JP> I didn't realize that for AM ,you might need a 500 foot antenna.  
 JP> Very interesting.

I'll have to see if the library carries that.  There was an article in the
current one that I wouldn't have minded browsing.  Not enough to buy the
magazine,  though.

Yeah,  AM could use something really long if you're gonna try and go for
some fraction of a wavelength,  but you can also do with a whole lot less. 
You do need a decent antenna,  though.  Our one car has a problem with the
antenna and it only works on FM,  only picks up one station halfway decent.
 AM doesn't work at all,  which is a pretty good indicator that there's
something wrong like a bad connection.

When you start getting into higher and higher frequencies RF starts getting
stranger and stranger,  where just a bit of circuit conductor acts like an
antenna,  or something else other than what you had intended.

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